diff --git a/bin/modoboa-admin.py b/bin/modoboa-admin.py
index 78de64d39..9c2a31270 100644
--- a/bin/modoboa-admin.py
+++ b/bin/modoboa-admin.py
@@ -1,8 +1,6 @@
 #!/usr/bin/env python
 # coding: utf-8
 
-from __future__ import unicode_literals
-
 from modoboa.core.commands import handle_command_line
 
 if __name__ == "__main__":
diff --git a/modoboa/__init__.py b/modoboa/__init__.py
index ad361c484..c9c4a76e9 100644
--- a/modoboa/__init__.py
+++ b/modoboa/__init__.py
@@ -2,8 +2,6 @@
 
 """Modoboa - Mail hosting made simple."""
 
-from __future__ import unicode_literals
-
 from pkg_resources import DistributionNotFound, get_distribution
 
 try:
diff --git a/modoboa/admin/__init__.py b/modoboa/admin/__init__.py
index 80f7ae2d3..8413b80d9 100644
--- a/modoboa/admin/__init__.py
+++ b/modoboa/admin/__init__.py
@@ -1,5 +1,3 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 default_app_config = "modoboa.admin.apps.AdminConfig"
diff --git a/modoboa/admin/api.py b/modoboa/admin/api.py
index 061637973..151a5bc9a 100644
--- a/modoboa/admin/api.py
+++ b/modoboa/admin/api.py
@@ -2,8 +2,6 @@
 
 """Admin API."""
 
-from __future__ import unicode_literals
-
 from django import http
 from django.contrib.contenttypes.models import ContentType
 
diff --git a/modoboa/admin/app_settings.py b/modoboa/admin/app_settings.py
index 8b343910a..6b3425557 100644
--- a/modoboa/admin/app_settings.py
+++ b/modoboa/admin/app_settings.py
@@ -2,8 +2,6 @@
 
 """Modoboa admin settings."""
 
-from __future__ import unicode_literals
-
 import os
 
 from django import forms
diff --git a/modoboa/admin/apps.py b/modoboa/admin/apps.py
index 77ba62271..a35b17974 100644
--- a/modoboa/admin/apps.py
+++ b/modoboa/admin/apps.py
@@ -2,8 +2,6 @@
 
 """AppConfig for admin."""
 
-from __future__ import unicode_literals
-
 from django.apps import AppConfig
 
 from .app_settings import load_admin_settings
diff --git a/modoboa/admin/constants.py b/modoboa/admin/constants.py
index 623d9b6b5..5526d1bf2 100644
--- a/modoboa/admin/constants.py
+++ b/modoboa/admin/constants.py
@@ -2,8 +2,6 @@
 
 """Admin constants."""
 
-from __future__ import unicode_literals
-
 from django.utils.translation import ugettext_lazy as _
 
 DNSBL_PROVIDERS = [
diff --git a/modoboa/admin/factories.py b/modoboa/admin/factories.py
index e0d5780c8..8e5a2cdb0 100644
--- a/modoboa/admin/factories.py
+++ b/modoboa/admin/factories.py
@@ -4,8 +4,6 @@
 Fixtures factories.
 """
 
-from __future__ import unicode_literals
-
 import factory
 
 from modoboa.core.factories import PermissionFactory, UserFactory
diff --git a/modoboa/admin/forms/__init__.py b/modoboa/admin/forms/__init__.py
index bb1ded79a..e5b5ee334 100644
--- a/modoboa/admin/forms/__init__.py
+++ b/modoboa/admin/forms/__init__.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 from .account import (
     AccountForm, AccountFormGeneral, AccountFormMail, AccountPermissionsForm,
     AccountWizard
diff --git a/modoboa/admin/forms/account.py b/modoboa/admin/forms/account.py
index 644ddabec..abbb0d183 100644
--- a/modoboa/admin/forms/account.py
+++ b/modoboa/admin/forms/account.py
@@ -2,8 +2,6 @@
 
 """Forms related to accounts management."""
 
-from __future__ import unicode_literals
-
 from collections import OrderedDict
 from functools import reduce
 
diff --git a/modoboa/admin/forms/alias.py b/modoboa/admin/forms/alias.py
index 09ee606e4..a7b874310 100644
--- a/modoboa/admin/forms/alias.py
+++ b/modoboa/admin/forms/alias.py
@@ -2,8 +2,6 @@
 
 """Forms related to aliases management."""
 
-from __future__ import unicode_literals
-
 from collections import OrderedDict
 
 from django import forms
diff --git a/modoboa/admin/forms/domain.py b/modoboa/admin/forms/domain.py
index 6a05eba45..69b2e1d69 100644
--- a/modoboa/admin/forms/domain.py
+++ b/modoboa/admin/forms/domain.py
@@ -2,8 +2,6 @@
 
 """Forms related to domains management."""
 
-from __future__ import unicode_literals
-
 from functools import reduce
 
 from django import forms
diff --git a/modoboa/admin/forms/export.py b/modoboa/admin/forms/export.py
index 1a295c599..90d3cdef9 100644
--- a/modoboa/admin/forms/export.py
+++ b/modoboa/admin/forms/export.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 from django import forms
 from django.utils.translation import ugettext_lazy
 
diff --git a/modoboa/admin/forms/forward.py b/modoboa/admin/forms/forward.py
index b270fb32d..a1c93d883 100644
--- a/modoboa/admin/forms/forward.py
+++ b/modoboa/admin/forms/forward.py
@@ -2,8 +2,6 @@
 
 """Forms related to forwards management."""
 
-from __future__ import unicode_literals
-
 from django import forms
 from django.core import validators
 from django.utils.translation import ugettext_lazy
diff --git a/modoboa/admin/forms/import_.py b/modoboa/admin/forms/import_.py
index db50913ff..b0741a894 100644
--- a/modoboa/admin/forms/import_.py
+++ b/modoboa/admin/forms/import_.py
@@ -2,8 +2,6 @@
 
 """Forms related to import operations."""
 
-from __future__ import unicode_literals
-
 from django import forms
 from django.utils.translation import ugettext_lazy
 
diff --git a/modoboa/admin/handlers.py b/modoboa/admin/handlers.py
index 2159f5dd8..4e4b91be7 100644
--- a/modoboa/admin/handlers.py
+++ b/modoboa/admin/handlers.py
@@ -2,8 +2,6 @@
 
 """Django signal handlers for admin."""
 
-from __future__ import unicode_literals
-
 from django.contrib.contenttypes.models import ContentType
 from django.db.models import signals
 from django.dispatch import receiver
diff --git a/modoboa/admin/lib.py b/modoboa/admin/lib.py
index f2ac6f556..59b4cf403 100644
--- a/modoboa/admin/lib.py
+++ b/modoboa/admin/lib.py
@@ -2,8 +2,6 @@
 
 """Internal library for admin."""
 
-from __future__ import unicode_literals
-
 import ipaddress
 import logging
 import random
diff --git a/modoboa/admin/management/commands/handle_mailbox_operations.py b/modoboa/admin/management/commands/handle_mailbox_operations.py
index 15d8f6e11..fead62ddc 100644
--- a/modoboa/admin/management/commands/handle_mailbox_operations.py
+++ b/modoboa/admin/management/commands/handle_mailbox_operations.py
@@ -2,8 +2,6 @@
 
 """A management command to apply mailbox operations."""
 
-from __future__ import print_function, unicode_literals
-
 import logging
 import os
 import shutil
diff --git a/modoboa/admin/management/commands/modo.py b/modoboa/admin/management/commands/modo.py
index b4f3495f5..5d6785428 100644
--- a/modoboa/admin/management/commands/modo.py
+++ b/modoboa/admin/management/commands/modo.py
@@ -2,8 +2,6 @@
 
 """Modoboa main management command."""
 
-from __future__ import unicode_literals
-
 from subcommand.base import SubcommandCommand
 
 from .subcommands._export import ExportCommand
diff --git a/modoboa/admin/management/commands/subcommands/_export.py b/modoboa/admin/management/commands/subcommands/_export.py
index 947f81d37..717ce2256 100644
--- a/modoboa/admin/management/commands/subcommands/_export.py
+++ b/modoboa/admin/management/commands/subcommands/_export.py
@@ -2,8 +2,6 @@
 
 """Django management command to export admin objects."""
 
-from __future__ import unicode_literals
-
 import sys
 
 from django.core.management.base import BaseCommand
diff --git a/modoboa/admin/management/commands/subcommands/_import.py b/modoboa/admin/management/commands/subcommands/_import.py
index a202fe22b..256ed36b3 100644
--- a/modoboa/admin/management/commands/subcommands/_import.py
+++ b/modoboa/admin/management/commands/subcommands/_import.py
@@ -2,8 +2,6 @@
 
 """Django management command to import admin objects."""
 
-from __future__ import unicode_literals
-
 import io
 import os
 
diff --git a/modoboa/admin/management/commands/subcommands/_manage_dkim_keys.py b/modoboa/admin/management/commands/subcommands/_manage_dkim_keys.py
index c7002c2c0..6fb58729b 100644
--- a/modoboa/admin/management/commands/subcommands/_manage_dkim_keys.py
+++ b/modoboa/admin/management/commands/subcommands/_manage_dkim_keys.py
@@ -2,8 +2,6 @@
 
 """Management command to create DKIM keys."""
 
-from __future__ import print_function, unicode_literals
-
 import os
 
 from django.core.management.base import BaseCommand
diff --git a/modoboa/admin/management/commands/subcommands/_mx.py b/modoboa/admin/management/commands/subcommands/_mx.py
index b88bd30a1..f669eb525 100644
--- a/modoboa/admin/management/commands/subcommands/_mx.py
+++ b/modoboa/admin/management/commands/subcommands/_mx.py
@@ -2,8 +2,6 @@
 
 """Management command to check defined domains."""
 
-from __future__ import print_function, unicode_literals
-
 import ipaddress
 
 import gevent
diff --git a/modoboa/admin/management/commands/subcommands/_repair.py b/modoboa/admin/management/commands/subcommands/_repair.py
index 26bfb42f4..2ef4f9431 100644
--- a/modoboa/admin/management/commands/subcommands/_repair.py
+++ b/modoboa/admin/management/commands/subcommands/_repair.py
@@ -2,8 +2,6 @@
 
 """Management command to check and fix known problems."""
 
-from __future__ import print_function, unicode_literals
-
 from django.conf import settings
 from django.core.management.base import BaseCommand
 from django.utils.encoding import smart_str
diff --git a/modoboa/admin/migrations/0001_initial.py b/modoboa/admin/migrations/0001_initial.py
index 9be649089..de9b7f214 100644
--- a/modoboa/admin/migrations/0001_initial.py
+++ b/modoboa/admin/migrations/0001_initial.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 from django.conf import settings
 
diff --git a/modoboa/admin/migrations/0002_migrate_from_modoboa_admin.py b/modoboa/admin/migrations/0002_migrate_from_modoboa_admin.py
index c854881b6..3ffa6fc06 100644
--- a/modoboa/admin/migrations/0002_migrate_from_modoboa_admin.py
+++ b/modoboa/admin/migrations/0002_migrate_from_modoboa_admin.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 
diff --git a/modoboa/admin/migrations/0003_auto_20151118_1215.py b/modoboa/admin/migrations/0003_auto_20151118_1215.py
index 3dbbfe390..a10568514 100644
--- a/modoboa/admin/migrations/0003_auto_20151118_1215.py
+++ b/modoboa/admin/migrations/0003_auto_20151118_1215.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/admin/migrations/0004_auto_20160914_0907.py b/modoboa/admin/migrations/0004_auto_20160914_0907.py
index 32aa5e148..7d9a56fdb 100644
--- a/modoboa/admin/migrations/0004_auto_20160914_0907.py
+++ b/modoboa/admin/migrations/0004_auto_20160914_0907.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.9.9 on 2016-09-14 09:07
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import django.db.models.deletion
 
diff --git a/modoboa/admin/migrations/0005_auto_20161026_1003.py b/modoboa/admin/migrations/0005_auto_20161026_1003.py
index d679eba6b..23888a98f 100644
--- a/modoboa/admin/migrations/0005_auto_20161026_1003.py
+++ b/modoboa/admin/migrations/0005_auto_20161026_1003.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.9.5 on 2016-10-26 08:03
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/admin/migrations/0006_auto_20161104_1900.py b/modoboa/admin/migrations/0006_auto_20161104_1900.py
index daac34e1b..d1ed561d6 100644
--- a/modoboa/admin/migrations/0006_auto_20161104_1900.py
+++ b/modoboa/admin/migrations/0006_auto_20161104_1900.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.9.5 on 2016-11-04 18:00
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import django.utils.timezone
 
diff --git a/modoboa/admin/migrations/0007_auto_20161104_1915.py b/modoboa/admin/migrations/0007_auto_20161104_1915.py
index 761a22a12..1a2061bed 100644
--- a/modoboa/admin/migrations/0007_auto_20161104_1915.py
+++ b/modoboa/admin/migrations/0007_auto_20161104_1915.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.9.5 on 2016-11-04 18:15
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/admin/migrations/0008_domain_enable_dns_checks.py b/modoboa/admin/migrations/0008_domain_enable_dns_checks.py
index c7be468fe..0377bf17c 100644
--- a/modoboa/admin/migrations/0008_domain_enable_dns_checks.py
+++ b/modoboa/admin/migrations/0008_domain_enable_dns_checks.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.9.12 on 2017-02-06 06:13
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/admin/migrations/0009_auto_20170215_0948.py b/modoboa/admin/migrations/0009_auto_20170215_0948.py
index b032a7190..c5a7dd820 100644
--- a/modoboa/admin/migrations/0009_auto_20170215_0948.py
+++ b/modoboa/admin/migrations/0009_auto_20170215_0948.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.10.5 on 2017-02-15 08:48
-from __future__ import unicode_literals
-
 from django.db import migrations
 
 
diff --git a/modoboa/admin/migrations/0010_auto_20170215_1328.py b/modoboa/admin/migrations/0010_auto_20170215_1328.py
index e71d408ca..5128c7e17 100644
--- a/modoboa/admin/migrations/0010_auto_20170215_1328.py
+++ b/modoboa/admin/migrations/0010_auto_20170215_1328.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.10.5 on 2017-02-15 12:28
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/admin/migrations/0011_domain_transport.py b/modoboa/admin/migrations/0011_domain_transport.py
index 8f037fb6c..168242c92 100644
--- a/modoboa/admin/migrations/0011_domain_transport.py
+++ b/modoboa/admin/migrations/0011_domain_transport.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.10.7 on 2017-12-20 14:17
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import django.db.models.deletion
 
diff --git a/modoboa/admin/migrations/0012_auto_20180112_1658.py b/modoboa/admin/migrations/0012_auto_20180112_1658.py
index a69e64388..f67dfa3c3 100644
--- a/modoboa/admin/migrations/0012_auto_20180112_1658.py
+++ b/modoboa/admin/migrations/0012_auto_20180112_1658.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.11.8 on 2018-01-12 15:58
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/admin/migrations/0013_auto_20180124_2311.py b/modoboa/admin/migrations/0013_auto_20180124_2311.py
index d0671ab0d..02194ff4b 100644
--- a/modoboa/admin/migrations/0013_auto_20180124_2311.py
+++ b/modoboa/admin/migrations/0013_auto_20180124_2311.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.11.8 on 2018-01-24 23:11
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/admin/migrations/0014_auto_20181017_1628.py b/modoboa/admin/migrations/0014_auto_20181017_1628.py
index ca7dee0c0..ae0fe2714 100644
--- a/modoboa/admin/migrations/0014_auto_20181017_1628.py
+++ b/modoboa/admin/migrations/0014_auto_20181017_1628.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.11.16 on 2018-10-17 14:28
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/admin/migrations/__init__.py b/modoboa/admin/migrations/__init__.py
index baffc4882..e69de29bb 100644
--- a/modoboa/admin/migrations/__init__.py
+++ b/modoboa/admin/migrations/__init__.py
@@ -1 +0,0 @@
-from __future__ import unicode_literals
diff --git a/modoboa/admin/models/__init__.py b/modoboa/admin/models/__init__.py
index 068fc45e9..70b16999f 100644
--- a/modoboa/admin/models/__init__.py
+++ b/modoboa/admin/models/__init__.py
@@ -2,8 +2,6 @@
 
 """Admin models."""
 
-from __future__ import unicode_literals
-
 from .alias import Alias, AliasRecipient
 from .base import AdminObject
 from .domain import Domain
diff --git a/modoboa/admin/models/alias.py b/modoboa/admin/models/alias.py
index 98a360c09..e76fb1c2a 100644
--- a/modoboa/admin/models/alias.py
+++ b/modoboa/admin/models/alias.py
@@ -2,8 +2,6 @@
 
 """Models related to aliases management."""
 
-from __future__ import unicode_literals
-
 import hashlib
 import random
 
diff --git a/modoboa/admin/models/base.py b/modoboa/admin/models/base.py
index abe182180..2ccf4638a 100644
--- a/modoboa/admin/models/base.py
+++ b/modoboa/admin/models/base.py
@@ -2,8 +2,6 @@
 
 """Base admin models."""
 
-from __future__ import unicode_literals
-
 from django.contrib.contenttypes.fields import GenericRelation
 from django.db import models
 from django.utils import timezone
diff --git a/modoboa/admin/models/domain.py b/modoboa/admin/models/domain.py
index a06932b87..fcd231538 100644
--- a/modoboa/admin/models/domain.py
+++ b/modoboa/admin/models/domain.py
@@ -2,8 +2,6 @@
 
 """Models related to domains management."""
 
-from __future__ import unicode_literals
-
 import datetime
 
 from reversion import revisions as reversion
diff --git a/modoboa/admin/models/domain_alias.py b/modoboa/admin/models/domain_alias.py
index 917039911..17186446e 100644
--- a/modoboa/admin/models/domain_alias.py
+++ b/modoboa/admin/models/domain_alias.py
@@ -2,8 +2,6 @@
 
 """Models related to domain aliases management."""
 
-from __future__ import unicode_literals
-
 from reversion import revisions as reversion
 
 from django.contrib.contenttypes.fields import GenericRelation
diff --git a/modoboa/admin/models/mailbox.py b/modoboa/admin/models/mailbox.py
index ef17ba264..eacd2c7a3 100644
--- a/modoboa/admin/models/mailbox.py
+++ b/modoboa/admin/models/mailbox.py
@@ -2,8 +2,6 @@
 
 """Models related to mailboxes management."""
 
-from __future__ import unicode_literals
-
 import os
 import pwd
 
diff --git a/modoboa/admin/models/mxrecord.py b/modoboa/admin/models/mxrecord.py
index 3d2cf9de8..66e3c1285 100644
--- a/modoboa/admin/models/mxrecord.py
+++ b/modoboa/admin/models/mxrecord.py
@@ -2,8 +2,6 @@
 
 """MX records storage."""
 
-from __future__ import unicode_literals
-
 import datetime
 
 from django.db import models
diff --git a/modoboa/admin/postfix_maps.py b/modoboa/admin/postfix_maps.py
index 1550fe7e6..6923ce8a6 100644
--- a/modoboa/admin/postfix_maps.py
+++ b/modoboa/admin/postfix_maps.py
@@ -2,9 +2,6 @@
 
 """Map file definitions for postfix."""
 
-from __future__ import unicode_literals
-
-
 class DomainsMap(object):
 
     """Map to list all domains."""
diff --git a/modoboa/admin/serializers.py b/modoboa/admin/serializers.py
index dfd3ed49b..65c30e54d 100644
--- a/modoboa/admin/serializers.py
+++ b/modoboa/admin/serializers.py
@@ -2,8 +2,6 @@
 
 """Admin serializers."""
 
-from __future__ import unicode_literals
-
 from django.conf import settings
 from django.contrib.auth import password_validation
 from django.core.exceptions import ValidationError
diff --git a/modoboa/admin/signals.py b/modoboa/admin/signals.py
index b085d7807..78d369f55 100644
--- a/modoboa/admin/signals.py
+++ b/modoboa/admin/signals.py
@@ -2,8 +2,6 @@
 
 """Modoboa admin signals."""
 
-from __future__ import unicode_literals
-
 import django.dispatch
 
 check_extra_account_form = django.dispatch.Signal(
diff --git a/modoboa/admin/templatetags/admin_tags.py b/modoboa/admin/templatetags/admin_tags.py
index 038eddb21..29aa0c459 100644
--- a/modoboa/admin/templatetags/admin_tags.py
+++ b/modoboa/admin/templatetags/admin_tags.py
@@ -2,8 +2,6 @@
 
 """Admin extension tags."""
 
-from __future__ import unicode_literals
-
 from functools import reduce
 
 from django import template
diff --git a/modoboa/admin/tests/test_account.py b/modoboa/admin/tests/test_account.py
index 10e43ca6b..7d816c46c 100644
--- a/modoboa/admin/tests/test_account.py
+++ b/modoboa/admin/tests/test_account.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 from unittest import skipIf
 
 from django.test import override_settings
diff --git a/modoboa/admin/tests/test_alias.py b/modoboa/admin/tests/test_alias.py
index b79ed39b6..3da7fc20b 100644
--- a/modoboa/admin/tests/test_alias.py
+++ b/modoboa/admin/tests/test_alias.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 from django.urls import reverse
 
 from modoboa.core.models import User
diff --git a/modoboa/admin/tests/test_api.py b/modoboa/admin/tests/test_api.py
index 235d6461c..e0a35823a 100644
--- a/modoboa/admin/tests/test_api.py
+++ b/modoboa/admin/tests/test_api.py
@@ -2,10 +2,9 @@
 
 """Admin API related tests."""
 
-from __future__ import unicode_literals
-
 import copy
 import json
+from unittest import mock
 
 import dns.resolver
 
@@ -20,13 +19,6 @@ from modoboa.lib.tests import ModoAPITestCase
 from . import utils
 from .. import factories, models
 
-try:
-    # mock is part of the Python (>= 3.3) standard library
-    from unittest import mock
-except ImportError:
-    # fall back to the mock backport
-    import mock
-
 
 class DomainAPITestCase(ModoAPITestCase):
     """Check API."""
diff --git a/modoboa/admin/tests/test_domain.py b/modoboa/admin/tests/test_domain.py
index 0f54ba663..fe1b3e260 100644
--- a/modoboa/admin/tests/test_domain.py
+++ b/modoboa/admin/tests/test_domain.py
@@ -2,11 +2,10 @@
 
 """Domain related test cases."""
 
-from __future__ import unicode_literals
-
 import os
 import shutil
 import tempfile
+from unittest import mock
 
 import dns.resolver
 from testfixtures import compare
@@ -23,13 +22,6 @@ from . import utils
 from .. import factories
 from ..models import Alias, Domain
 
-try:
-    # mock is part of the Python (>= 3.3) standard library
-    from unittest import mock
-except ImportError:
-    # fall back to the mock backport
-    import mock
-
 
 class DomainTestCase(ModoTestCase):
     """Test case for Domain."""
diff --git a/modoboa/admin/tests/test_domain_alias.py b/modoboa/admin/tests/test_domain_alias.py
index d02e4ef96..cb3165f03 100644
--- a/modoboa/admin/tests/test_domain_alias.py
+++ b/modoboa/admin/tests/test_domain_alias.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 from django.urls import reverse
 
 from modoboa.lib.tests import ModoTestCase
diff --git a/modoboa/admin/tests/test_export.py b/modoboa/admin/tests/test_export.py
index c261520b7..2d0ece78a 100644
--- a/modoboa/admin/tests/test_export.py
+++ b/modoboa/admin/tests/test_export.py
@@ -2,8 +2,6 @@
 
 """Export related test cases."""
 
-from __future__ import unicode_literals
-
 import sys
 
 from six.moves import StringIO
diff --git a/modoboa/admin/tests/test_import_.py b/modoboa/admin/tests/test_import_.py
index aa0a5eaad..e062e1032 100644
--- a/modoboa/admin/tests/test_import_.py
+++ b/modoboa/admin/tests/test_import_.py
@@ -1,8 +1,7 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 import os
+from unittest import mock
 
 import dns.resolver
 
@@ -18,13 +17,6 @@ from . import utils
 from .. import factories
 from ..models import Alias, Domain, DomainAlias
 
-try:
-    # mock is part of the Python (>= 3.3) standard library
-    from unittest import mock
-except ImportError:
-    # fall back to the mock backport
-    import mock
-
 
 class ImportTestCase(ModoTestCase):
 
diff --git a/modoboa/admin/tests/test_mailbox_operations.py b/modoboa/admin/tests/test_mailbox_operations.py
index 6e598bb57..101bf3e12 100644
--- a/modoboa/admin/tests/test_mailbox_operations.py
+++ b/modoboa/admin/tests/test_mailbox_operations.py
@@ -2,11 +2,10 @@
 
 """Management command tests."""
 
-from __future__ import unicode_literals
-
 import os
 import shutil
 import tempfile
+from unittest import mock
 
 from django.core.management import call_command
 from django.test import override_settings
@@ -15,13 +14,6 @@ from django.urls import reverse
 from modoboa.lib.tests import ModoTestCase
 from .. import factories, models
 
-try:
-    # mock is part of the Python (>= 3.3) standard library
-    from unittest import mock
-except ImportError:
-    # fall back to the mock backport
-    import mock
-
 
 @override_settings(
     DOVECOT_LOOKUP_PATH=["{}/dovecot".format(os.path.dirname(__file__))])
diff --git a/modoboa/admin/tests/test_mapfiles.py b/modoboa/admin/tests/test_mapfiles.py
index 1da822f04..8b43a0016 100644
--- a/modoboa/admin/tests/test_mapfiles.py
+++ b/modoboa/admin/tests/test_mapfiles.py
@@ -2,8 +2,6 @@
 
 """Test map files generation."""
 
-from __future__ import unicode_literals
-
 import os
 
 from django.conf import settings
diff --git a/modoboa/admin/tests/test_mx.py b/modoboa/admin/tests/test_mx.py
index 183ae8382..08e1ff33e 100644
--- a/modoboa/admin/tests/test_mx.py
+++ b/modoboa/admin/tests/test_mx.py
@@ -2,7 +2,7 @@
 
 """DNSBL related tests."""
 
-from __future__ import unicode_literals
+from unittest import mock
 
 import dns.resolver
 from testfixtures import LogCapture
@@ -18,13 +18,6 @@ from . import utils
 from .. import factories, models
 from ..lib import get_domain_mx_list
 
-try:
-    # mock is part of the Python (>= 3.3) standard library
-    from unittest import mock
-except ImportError:
-    # fall back to the mock backport
-    import mock
-
 
 class MXTestCase(ModoTestCase):
     """TestCase for DNSBL related features."""
diff --git a/modoboa/admin/tests/test_password_schemes.py b/modoboa/admin/tests/test_password_schemes.py
index 61b83b14a..0718cf76c 100644
--- a/modoboa/admin/tests/test_password_schemes.py
+++ b/modoboa/admin/tests/test_password_schemes.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 from django.urls import reverse
 
 from modoboa.core.models import User
diff --git a/modoboa/admin/tests/test_repair.py b/modoboa/admin/tests/test_repair.py
index 1a45225b0..1cedf23c3 100644
--- a/modoboa/admin/tests/test_repair.py
+++ b/modoboa/admin/tests/test_repair.py
@@ -2,8 +2,6 @@
 
 """Repair command tests"""
 
-from __future__ import unicode_literals
-
 from django.core import management
 
 from modoboa.lib.permissions import ObjectAccess, get_object_owner
diff --git a/modoboa/admin/tests/test_user.py b/modoboa/admin/tests/test_user.py
index 3e2238355..cfaf5fd53 100644
--- a/modoboa/admin/tests/test_user.py
+++ b/modoboa/admin/tests/test_user.py
@@ -2,8 +2,6 @@
 
 """User related tests."""
 
-from __future__ import unicode_literals
-
 from django.urls import reverse
 
 from modoboa.core.models import User
diff --git a/modoboa/admin/tests/utils.py b/modoboa/admin/tests/utils.py
index f0662d5ec..0f604196d 100644
--- a/modoboa/admin/tests/utils.py
+++ b/modoboa/admin/tests/utils.py
@@ -2,8 +2,6 @@
 
 """Test utilities."""
 
-from __future__ import unicode_literals
-
 import socket
 
 from dns.name import Name
diff --git a/modoboa/admin/urls.py b/modoboa/admin/urls.py
index bb299ae19..1545855e3 100644
--- a/modoboa/admin/urls.py
+++ b/modoboa/admin/urls.py
@@ -2,8 +2,6 @@
 
 """Admin urls."""
 
-from __future__ import unicode_literals
-
 from django.conf.urls import url
 
 from . import views
diff --git a/modoboa/admin/urls_api.py b/modoboa/admin/urls_api.py
index 4227d9cfa..9c3889bb8 100644
--- a/modoboa/admin/urls_api.py
+++ b/modoboa/admin/urls_api.py
@@ -2,8 +2,6 @@
 
 """Admin API urls."""
 
-from __future__ import unicode_literals
-
 from rest_framework import routers
 
 from . import api
diff --git a/modoboa/admin/views/__init__.py b/modoboa/admin/views/__init__.py
index 501c59517..694d83979 100644
--- a/modoboa/admin/views/__init__.py
+++ b/modoboa/admin/views/__init__.py
@@ -2,8 +2,6 @@
 
 """Shortcuts."""
 
-from __future__ import unicode_literals
-
 from .alias import AliasDetailView
 from .dns import DNSBLDomainDetailView, MXDomainDetailView
 from .domain import DomainDetailView
diff --git a/modoboa/admin/views/alias.py b/modoboa/admin/views/alias.py
index 9b3dfb1c6..4246fdb05 100644
--- a/modoboa/admin/views/alias.py
+++ b/modoboa/admin/views/alias.py
@@ -2,8 +2,6 @@
 
 """Alias related views."""
 
-from __future__ import unicode_literals
-
 from reversion import revisions as reversion
 
 from django.contrib.auth import mixins as auth_mixins
diff --git a/modoboa/admin/views/dns.py b/modoboa/admin/views/dns.py
index e202bb818..6dc373b82 100644
--- a/modoboa/admin/views/dns.py
+++ b/modoboa/admin/views/dns.py
@@ -2,8 +2,6 @@
 
 """DNSBL related views."""
 
-from __future__ import unicode_literals
-
 from django.contrib.auth import mixins as auth_mixins
 from django.utils.translation import ugettext as _
 from django.views import generic
diff --git a/modoboa/admin/views/domain.py b/modoboa/admin/views/domain.py
index b30e29ed6..c83b1f036 100644
--- a/modoboa/admin/views/domain.py
+++ b/modoboa/admin/views/domain.py
@@ -2,8 +2,6 @@
 
 """Domain related views."""
 
-from __future__ import unicode_literals
-
 from functools import reduce
 
 from reversion import revisions as reversion
diff --git a/modoboa/admin/views/export.py b/modoboa/admin/views/export.py
index 281d864d3..d28fcac6c 100644
--- a/modoboa/admin/views/export.py
+++ b/modoboa/admin/views/export.py
@@ -2,8 +2,6 @@
 
 """Export related views."""
 
-from __future__ import unicode_literals
-
 from rfc6266 import build_header
 
 from django.contrib.auth.decorators import (
diff --git a/modoboa/admin/views/identity.py b/modoboa/admin/views/identity.py
index 62ce47d58..f223944ec 100644
--- a/modoboa/admin/views/identity.py
+++ b/modoboa/admin/views/identity.py
@@ -2,8 +2,6 @@
 
 """Identity related views."""
 
-from __future__ import unicode_literals
-
 from reversion import revisions as reversion
 
 from django.contrib.auth import mixins as auth_mixins
diff --git a/modoboa/admin/views/import_.py b/modoboa/admin/views/import_.py
index 025d9d0e3..61800bce1 100644
--- a/modoboa/admin/views/import_.py
+++ b/modoboa/admin/views/import_.py
@@ -2,8 +2,6 @@
 
 """Import related views."""
 
-from __future__ import unicode_literals
-
 import io
 
 from reversion import revisions as reversion
diff --git a/modoboa/admin/views/user.py b/modoboa/admin/views/user.py
index cb9e18d12..483154492 100644
--- a/modoboa/admin/views/user.py
+++ b/modoboa/admin/views/user.py
@@ -2,8 +2,6 @@
 
 """SimpleUsers views."""
 
-from __future__ import unicode_literals
-
 from reversion import revisions as reversion
 
 from django.contrib.auth.decorators import login_required
diff --git a/modoboa/core/__init__.py b/modoboa/core/__init__.py
index 4efbc2ba0..b6722abab 100644
--- a/modoboa/core/__init__.py
+++ b/modoboa/core/__init__.py
@@ -2,6 +2,4 @@
 
 """App config for core."""
 
-from __future__ import unicode_literals
-
 default_app_config = "modoboa.core.apps.CoreConfig"
diff --git a/modoboa/core/app_settings.py b/modoboa/core/app_settings.py
index f63f045da..5388f13e1 100644
--- a/modoboa/core/app_settings.py
+++ b/modoboa/core/app_settings.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 from django import forms
 from django.conf import settings
 from django.contrib.auth import password_validation
diff --git a/modoboa/core/apps.py b/modoboa/core/apps.py
index 3e4fa2859..997550481 100644
--- a/modoboa/core/apps.py
+++ b/modoboa/core/apps.py
@@ -2,8 +2,6 @@
 
 """Core config for admin."""
 
-from __future__ import unicode_literals
-
 from django.apps import AppConfig
 from django.db.models import signals
 from django.utils.translation import ugettext_lazy
diff --git a/modoboa/core/checks/__init__.py b/modoboa/core/checks/__init__.py
index c043b6cf9..e41b8f04b 100644
--- a/modoboa/core/checks/__init__.py
+++ b/modoboa/core/checks/__init__.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 # Import these to force registration of checks
 from . import settings_checks  # NOQA:F401
diff --git a/modoboa/core/checks/settings_checks.py b/modoboa/core/checks/settings_checks.py
index ebd09db14..39f82e2c9 100644
--- a/modoboa/core/checks/settings_checks.py
+++ b/modoboa/core/checks/settings_checks.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 from django.conf import settings
 from django.core.checks import Warning, register
 from django.utils.translation import ugettext as _
diff --git a/modoboa/core/commands/__init__.py b/modoboa/core/commands/__init__.py
index 9a07357ce..04fb4640a 100644
--- a/modoboa/core/commands/__init__.py
+++ b/modoboa/core/commands/__init__.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import print_function, unicode_literals
-
 import argparse
 import os
 import sys
diff --git a/modoboa/core/commands/deploy.py b/modoboa/core/commands/deploy.py
index 25c81c2e1..5c82803f9 100644
--- a/modoboa/core/commands/deploy.py
+++ b/modoboa/core/commands/deploy.py
@@ -2,8 +2,6 @@
 
 """A shortcut to deploy a fresh modoboa instance."""
 
-from __future__ import print_function, unicode_literals
-
 import codecs
 import getpass
 import os
diff --git a/modoboa/core/commands/help.py b/modoboa/core/commands/help.py
index 931264615..d1c6d387f 100644
--- a/modoboa/core/commands/help.py
+++ b/modoboa/core/commands/help.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import print_function, unicode_literals
-
 import sys
 
 from . import Command
diff --git a/modoboa/core/commands/templates/settings.py.tpl b/modoboa/core/commands/templates/settings.py.tpl
index cfd0fc5b7..fd9605784 100644
--- a/modoboa/core/commands/templates/settings.py.tpl
+++ b/modoboa/core/commands/templates/settings.py.tpl
@@ -9,8 +9,6 @@ For the full list of settings and their values, see
 https://docs.djangoproject.com/en/1.11/ref/settings/
 """
 
-from __future__ import unicode_literals
-
 from logging.handlers import SysLogHandler
 import os
 {% if devmode %}
diff --git a/modoboa/core/constants.py b/modoboa/core/constants.py
index b333e61fd..007a549d2 100644
--- a/modoboa/core/constants.py
+++ b/modoboa/core/constants.py
@@ -2,8 +2,6 @@
 
 """Core application constants."""
 
-from __future__ import unicode_literals
-
 from django.utils.translation import ugettext_lazy
 
 SIMPLEUSERS_ROLE = ("SimpleUsers", ugettext_lazy("Simple user"))
diff --git a/modoboa/core/context_processors.py b/modoboa/core/context_processors.py
index 501b2cdc5..ba348fe3b 100644
--- a/modoboa/core/context_processors.py
+++ b/modoboa/core/context_processors.py
@@ -2,8 +2,6 @@
 
 """Custom context processors."""
 
-from __future__ import unicode_literals
-
 from functools import reduce
 
 from . import signals
diff --git a/modoboa/core/dev_settings.py b/modoboa/core/dev_settings.py
index c443d5965..eb5ae7c09 100644
--- a/modoboa/core/dev_settings.py
+++ b/modoboa/core/dev_settings.py
@@ -2,8 +2,6 @@
 
 # Development settings
 
-from __future__ import unicode_literals
-
 import os
 
 BOWER_COMPONENTS_ROOT = os.path.join(
diff --git a/modoboa/core/extensions.py b/modoboa/core/extensions.py
index c0287745e..95207cec1 100644
--- a/modoboa/core/extensions.py
+++ b/modoboa/core/extensions.py
@@ -2,8 +2,6 @@
 
 """Extension management."""
 
-from __future__ import unicode_literals
-
 from django.conf import settings
 from django.conf.urls import include, url
 from django.utils.encoding import smart_str
diff --git a/modoboa/core/factories.py b/modoboa/core/factories.py
index e0ad3315f..136c29c96 100644
--- a/modoboa/core/factories.py
+++ b/modoboa/core/factories.py
@@ -2,8 +2,6 @@
 
 """Factories for core application."""
 
-from __future__ import unicode_literals
-
 import factory
 
 from django.contrib.auth.models import Group
diff --git a/modoboa/core/forms.py b/modoboa/core/forms.py
index 78e1f3e08..a7b2b764a 100644
--- a/modoboa/core/forms.py
+++ b/modoboa/core/forms.py
@@ -2,8 +2,6 @@
 
 """Core forms."""
 
-from __future__ import unicode_literals
-
 from django import forms
 from django.contrib.auth import (
     forms as auth_forms, get_user_model, password_validation
diff --git a/modoboa/core/handlers.py b/modoboa/core/handlers.py
index c964861a7..ed1bce204 100644
--- a/modoboa/core/handlers.py
+++ b/modoboa/core/handlers.py
@@ -2,8 +2,6 @@
 
 """Modoboa core signal handlers."""
 
-from __future__ import unicode_literals
-
 import logging
 
 from reversion import revisions as reversion
diff --git a/modoboa/core/loggers.py b/modoboa/core/loggers.py
index 9090f5999..889f721f7 100644
--- a/modoboa/core/loggers.py
+++ b/modoboa/core/loggers.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 import logging
 
 
diff --git a/modoboa/core/management/commands/clean_inactive_accounts.py b/modoboa/core/management/commands/clean_inactive_accounts.py
index c67d21358..1891905b3 100644
--- a/modoboa/core/management/commands/clean_inactive_accounts.py
+++ b/modoboa/core/management/commands/clean_inactive_accounts.py
@@ -2,8 +2,6 @@
 
 """Inactive accounts cleanup tool."""
 
-from __future__ import print_function, unicode_literals
-
 from dateutil.relativedelta import relativedelta
 from six.moves import input
 
diff --git a/modoboa/core/management/commands/cleanlogs.py b/modoboa/core/management/commands/cleanlogs.py
index 723cdf9c0..f198e1a67 100644
--- a/modoboa/core/management/commands/cleanlogs.py
+++ b/modoboa/core/management/commands/cleanlogs.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import print_function, unicode_literals
-
 import datetime
 import logging
 
diff --git a/modoboa/core/management/commands/communicate_with_public_api.py b/modoboa/core/management/commands/communicate_with_public_api.py
index 2fe2359c8..10f37a4e8 100644
--- a/modoboa/core/management/commands/communicate_with_public_api.py
+++ b/modoboa/core/management/commands/communicate_with_public_api.py
@@ -2,8 +2,6 @@
 
 """Management command to communicate with public API."""
 
-from __future__ import unicode_literals
-
 from django.core.management.base import BaseCommand, CommandError
 
 from modoboa.admin import models as admin_models
diff --git a/modoboa/core/management/commands/generate_postfix_maps.py b/modoboa/core/management/commands/generate_postfix_maps.py
index b76fb289b..c5f692cbd 100644
--- a/modoboa/core/management/commands/generate_postfix_maps.py
+++ b/modoboa/core/management/commands/generate_postfix_maps.py
@@ -2,8 +2,6 @@
 
 """Management command to generate/update postfix map files."""
 
-from __future__ import print_function, unicode_literals
-
 import copy
 import hashlib
 import os
diff --git a/modoboa/core/management/commands/load_initial_data.py b/modoboa/core/management/commands/load_initial_data.py
index d43f27bfc..36ba54bc0 100644
--- a/modoboa/core/management/commands/load_initial_data.py
+++ b/modoboa/core/management/commands/load_initial_data.py
@@ -7,8 +7,6 @@
 
 """
 
-from __future__ import unicode_literals
-
 from functools import reduce
 
 from django.contrib.auth.models import Group
diff --git a/modoboa/core/management/commands/set_default_site.py b/modoboa/core/management/commands/set_default_site.py
index 8080420bc..02c66e6fb 100644
--- a/modoboa/core/management/commands/set_default_site.py
+++ b/modoboa/core/management/commands/set_default_site.py
@@ -6,8 +6,6 @@ A simple managemenent command to update the default site.
 See `https://docs.djangoproject.com/en/dev/ref/contrib/sites/`_.
 """
 
-from __future__ import unicode_literals
-
 from django.contrib.sites.models import Site
 from django.core.management.base import BaseCommand, CommandError
 
diff --git a/modoboa/core/middleware.py b/modoboa/core/middleware.py
index 65135942f..b80bf6a1b 100644
--- a/modoboa/core/middleware.py
+++ b/modoboa/core/middleware.py
@@ -2,8 +2,6 @@
 
 """Core middlewares."""
 
-from __future__ import unicode_literals
-
 from django.utils.deprecation import MiddlewareMixin
 
 from . import models
diff --git a/modoboa/core/migrations/0001_initial.py b/modoboa/core/migrations/0001_initial.py
index 1be0eae38..b937f896b 100644
--- a/modoboa/core/migrations/0001_initial.py
+++ b/modoboa/core/migrations/0001_initial.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 import django.utils.timezone
 from django.conf import settings
diff --git a/modoboa/core/migrations/0002_delete_extension.py b/modoboa/core/migrations/0002_delete_extension.py
index 073ef44bb..23ad4ba2e 100644
--- a/modoboa/core/migrations/0002_delete_extension.py
+++ b/modoboa/core/migrations/0002_delete_extension.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 
diff --git a/modoboa/core/migrations/0003_user_master_user.py b/modoboa/core/migrations/0003_user_master_user.py
index 9411bdd5c..ed5316dc1 100644
--- a/modoboa/core/migrations/0003_user_master_user.py
+++ b/modoboa/core/migrations/0003_user_master_user.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 
diff --git a/modoboa/core/migrations/0004_auto_20150728_1228.py b/modoboa/core/migrations/0004_auto_20150728_1228.py
index 202a23da0..36856458f 100644
--- a/modoboa/core/migrations/0004_auto_20150728_1228.py
+++ b/modoboa/core/migrations/0004_auto_20150728_1228.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 
diff --git a/modoboa/core/migrations/0005_user_language.py b/modoboa/core/migrations/0005_user_language.py
index 3f61578ca..55bbec01d 100644
--- a/modoboa/core/migrations/0005_user_language.py
+++ b/modoboa/core/migrations/0005_user_language.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 
diff --git a/modoboa/core/migrations/0006_auto_20151114_1518.py b/modoboa/core/migrations/0006_auto_20151114_1518.py
index e3c1b88af..36acdbbdf 100644
--- a/modoboa/core/migrations/0006_auto_20151114_1518.py
+++ b/modoboa/core/migrations/0006_auto_20151114_1518.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 
diff --git a/modoboa/core/migrations/0007_auto_20151116_1349.py b/modoboa/core/migrations/0007_auto_20151116_1349.py
index b7d45d14d..94ceca391 100644
--- a/modoboa/core/migrations/0007_auto_20151116_1349.py
+++ b/modoboa/core/migrations/0007_auto_20151116_1349.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import django.contrib.auth.models
 
diff --git a/modoboa/core/migrations/0008_localconfig.py b/modoboa/core/migrations/0008_localconfig.py
index be8040af8..4923bd055 100644
--- a/modoboa/core/migrations/0008_localconfig.py
+++ b/modoboa/core/migrations/0008_localconfig.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.9.5 on 2016-06-15 18:12
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import django.db.models.deletion
 import jsonfield.fields
diff --git a/modoboa/core/migrations/0009_auto_20161026_1003.py b/modoboa/core/migrations/0009_auto_20161026_1003.py
index 51aa18ed8..37f0b47f4 100644
--- a/modoboa/core/migrations/0009_auto_20161026_1003.py
+++ b/modoboa/core/migrations/0009_auto_20161026_1003.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.9.5 on 2016-10-26 08:03
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/core/migrations/0010_auto_20161026_1011.py b/modoboa/core/migrations/0010_auto_20161026_1011.py
index 64961f261..ed0bb5346 100644
--- a/modoboa/core/migrations/0010_auto_20161026_1011.py
+++ b/modoboa/core/migrations/0010_auto_20161026_1011.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.9.5 on 2016-10-26 08:11
-from __future__ import unicode_literals
-
 from django.db import migrations
 import jsonfield.fields
 
diff --git a/modoboa/core/migrations/0011_auto_20161104_2217.py b/modoboa/core/migrations/0011_auto_20161104_2217.py
index 44006a607..b3680de4f 100644
--- a/modoboa/core/migrations/0011_auto_20161104_2217.py
+++ b/modoboa/core/migrations/0011_auto_20161104_2217.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.9.5 on 2016-11-04 21:17
-from __future__ import unicode_literals
-
 from django.db import migrations
 import jsonfield.fields
 
diff --git a/modoboa/core/migrations/0012_auto_20170215_1034.py b/modoboa/core/migrations/0012_auto_20170215_1034.py
index 51e0fd7d3..0134f15f8 100644
--- a/modoboa/core/migrations/0012_auto_20170215_1034.py
+++ b/modoboa/core/migrations/0012_auto_20170215_1034.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.10.5 on 2017-02-15 09:34
-from __future__ import unicode_literals
-
 from django.db import migrations
 
 
diff --git a/modoboa/core/migrations/0013_auto_20170707_1058.py b/modoboa/core/migrations/0013_auto_20170707_1058.py
index 934a30898..edccb37c7 100644
--- a/modoboa/core/migrations/0013_auto_20170707_1058.py
+++ b/modoboa/core/migrations/0013_auto_20170707_1058.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.10.7 on 2017-07-07 08:58
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import django.utils.timezone
 
diff --git a/modoboa/core/migrations/0014_auto_20171010_1746.py b/modoboa/core/migrations/0014_auto_20171010_1746.py
index 698772236..aa00a9b60 100644
--- a/modoboa/core/migrations/0014_auto_20171010_1746.py
+++ b/modoboa/core/migrations/0014_auto_20171010_1746.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.10.7 on 2017-10-10 15:46
-from __future__ import unicode_literals
-
 from django.db import migrations
 
 
diff --git a/modoboa/core/migrations/0015_auto_20180112_1642.py b/modoboa/core/migrations/0015_auto_20180112_1642.py
index d253aaa52..b2ad1956d 100644
--- a/modoboa/core/migrations/0015_auto_20180112_1642.py
+++ b/modoboa/core/migrations/0015_auto_20180112_1642.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.11.8 on 2018-01-12 15:42
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/core/migrations/0016_auto_20180713_1014.py b/modoboa/core/migrations/0016_auto_20180713_1014.py
index 2315c2a03..58b36bd7a 100644
--- a/modoboa/core/migrations/0016_auto_20180713_1014.py
+++ b/modoboa/core/migrations/0016_auto_20180713_1014.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.11.11 on 2018-07-13 08:14
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/core/migrations/0017_auto_20190705_1045.py b/modoboa/core/migrations/0017_auto_20190705_1045.py
index 887a8fc8f..fe2a24d31 100644
--- a/modoboa/core/migrations/0017_auto_20190705_1045.py
+++ b/modoboa/core/migrations/0017_auto_20190705_1045.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.11.18 on 2019-07-05 08:45
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/core/migrations/__init__.py b/modoboa/core/migrations/__init__.py
index baffc4882..e69de29bb 100644
--- a/modoboa/core/migrations/__init__.py
+++ b/modoboa/core/migrations/__init__.py
@@ -1 +0,0 @@
-from __future__ import unicode_literals
diff --git a/modoboa/core/mocks.py b/modoboa/core/mocks.py
index 53044082b..e2414591a 100644
--- a/modoboa/core/mocks.py
+++ b/modoboa/core/mocks.py
@@ -2,8 +2,6 @@
 
 """Mocks used for testing."""
 
-from __future__ import unicode_literals
-
 import httmock
 
 # Modoboa API mocks
diff --git a/modoboa/core/models.py b/modoboa/core/models.py
index 18ed79d5f..2f3fb6bc2 100644
--- a/modoboa/core/models.py
+++ b/modoboa/core/models.py
@@ -2,8 +2,6 @@
 
 """Core models."""
 
-from __future__ import unicode_literals
-
 import re
 from email.header import Header
 
diff --git a/modoboa/core/password_hashers/__init__.py b/modoboa/core/password_hashers/__init__.py
index 2af1b766f..4104cb749 100644
--- a/modoboa/core/password_hashers/__init__.py
+++ b/modoboa/core/password_hashers/__init__.py
@@ -4,8 +4,6 @@
 Password hashers for Modoboa.
 """
 
-from __future__ import unicode_literals
-
 from django.utils.encoding import smart_text
 
 from modoboa.core.password_hashers.advanced import (  # NOQA:F401
diff --git a/modoboa/core/password_hashers/advanced.py b/modoboa/core/password_hashers/advanced.py
index 1c0a4bd71..f42c13423 100644
--- a/modoboa/core/password_hashers/advanced.py
+++ b/modoboa/core/password_hashers/advanced.py
@@ -6,8 +6,6 @@ Advanced (ie. stronger) password hashers.
 This module relies on `passlib` to provide more secure hashers.
 """
 
-from __future__ import unicode_literals
-
 from passlib.hash import bcrypt, md5_crypt, sha256_crypt, sha512_crypt
 
 try:
diff --git a/modoboa/core/password_hashers/base.py b/modoboa/core/password_hashers/base.py
index 8b354466f..4cce37e5e 100644
--- a/modoboa/core/password_hashers/base.py
+++ b/modoboa/core/password_hashers/base.py
@@ -6,8 +6,6 @@ Base password hashers.
 Contains weak hashers (the original ones) available with Modoboa.
 """
 
-from __future__ import unicode_literals
-
 import base64
 import crypt
 import hashlib
diff --git a/modoboa/core/password_validation.py b/modoboa/core/password_validation.py
index db3693ba1..de5df3f97 100644
--- a/modoboa/core/password_validation.py
+++ b/modoboa/core/password_validation.py
@@ -2,8 +2,6 @@
 
 """Custom password validators."""
 
-from __future__ import unicode_literals
-
 from django.core.exceptions import ValidationError
 from django.utils.translation import ugettext as _, ungettext
 
diff --git a/modoboa/core/signals.py b/modoboa/core/signals.py
index 708759fac..a52809352 100644
--- a/modoboa/core/signals.py
+++ b/modoboa/core/signals.py
@@ -2,8 +2,6 @@
 
 """Modoboa core signals."""
 
-from __future__ import unicode_literals
-
 import django.dispatch
 
 account_auto_created = django.dispatch.Signal(providing_args=["user"])
diff --git a/modoboa/core/templatetags/core_tags.py b/modoboa/core/templatetags/core_tags.py
index b0f98ca3c..a160e62fc 100644
--- a/modoboa/core/templatetags/core_tags.py
+++ b/modoboa/core/templatetags/core_tags.py
@@ -2,8 +2,6 @@
 
 """Custom tags for Core application."""
 
-from __future__ import unicode_literals
-
 import os
 import re
 from functools import reduce
diff --git a/modoboa/core/tests/stupid_extension_1/modo_extension.py b/modoboa/core/tests/stupid_extension_1/modo_extension.py
index 5fdf23318..c35c87937 100644
--- a/modoboa/core/tests/stupid_extension_1/modo_extension.py
+++ b/modoboa/core/tests/stupid_extension_1/modo_extension.py
@@ -2,8 +2,6 @@
 
 """A stupid extension used for tests."""
 
-from __future__ import unicode_literals
-
 from modoboa.core import extensions
 
 
diff --git a/modoboa/core/tests/stupid_extension_2/modo_extension.py b/modoboa/core/tests/stupid_extension_2/modo_extension.py
index c7a58d1cc..f44a359ee 100644
--- a/modoboa/core/tests/stupid_extension_2/modo_extension.py
+++ b/modoboa/core/tests/stupid_extension_2/modo_extension.py
@@ -2,8 +2,6 @@
 
 """A stupid extension used for tests."""
 
-from __future__ import unicode_literals
-
 from modoboa.core import extensions
 
 
diff --git a/modoboa/core/tests/stupid_extension_2/urls.py b/modoboa/core/tests/stupid_extension_2/urls.py
index 0e3717f91..b0a58d9b5 100644
--- a/modoboa/core/tests/stupid_extension_2/urls.py
+++ b/modoboa/core/tests/stupid_extension_2/urls.py
@@ -2,8 +2,6 @@
 
 """Custom urls."""
 
-from __future__ import unicode_literals
-
 from django.conf.urls import url
 
 from . import views
diff --git a/modoboa/core/tests/stupid_extension_2/views.py b/modoboa/core/tests/stupid_extension_2/views.py
index c0a372402..127ace10b 100644
--- a/modoboa/core/tests/stupid_extension_2/views.py
+++ b/modoboa/core/tests/stupid_extension_2/views.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 from django import http
 
 
diff --git a/modoboa/core/tests/test_authentication.py b/modoboa/core/tests/test_authentication.py
index 912855f4c..3c5fe0c2f 100644
--- a/modoboa/core/tests/test_authentication.py
+++ b/modoboa/core/tests/test_authentication.py
@@ -2,11 +2,9 @@
 
 """Tests for core application."""
 
-from __future__ import unicode_literals
-
 import os
 import smtplib
-from unittest import skipIf, skipUnless
+from unittest import mock, skipIf, skipUnless
 
 from django.core import mail
 from django.test import override_settings
@@ -23,13 +21,6 @@ from modoboa.core.password_hashers import (
 from modoboa.lib.tests import NO_SMTP, ModoTestCase
 from .. import factories, models
 
-try:
-    # mock is part of the Python (>= 3.3) standard library
-    from unittest import mock
-except ImportError:
-    # fall back to the mock backport
-    import mock
-
 
 @override_settings(
     DOVEADM_LOOKUP_PATH=["{}/doveadm".format(os.path.dirname(__file__))])
diff --git a/modoboa/core/tests/test_checks.py b/modoboa/core/tests/test_checks.py
index 124cf3930..da4d1977e 100644
--- a/modoboa/core/tests/test_checks.py
+++ b/modoboa/core/tests/test_checks.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 from django.test import SimpleTestCase
 from django.test.utils import override_settings
 
diff --git a/modoboa/core/tests/test_core.py b/modoboa/core/tests/test_core.py
index 5d9a5a605..95772de16 100644
--- a/modoboa/core/tests/test_core.py
+++ b/modoboa/core/tests/test_core.py
@@ -2,8 +2,6 @@
 
 """Tests for core application."""
 
-from __future__ import unicode_literals
-
 import httmock
 from dateutil.relativedelta import relativedelta
 from six import StringIO
diff --git a/modoboa/core/tests/test_extensions.py b/modoboa/core/tests/test_extensions.py
index af420f526..74116b87b 100644
--- a/modoboa/core/tests/test_extensions.py
+++ b/modoboa/core/tests/test_extensions.py
@@ -2,8 +2,6 @@
 
 """Extensions management related test cases."""
 
-from __future__ import unicode_literals
-
 import os
 import sys
 
diff --git a/modoboa/core/tests/test_ldap.py b/modoboa/core/tests/test_ldap.py
index 54c12a31a..8e4bdf410 100644
--- a/modoboa/core/tests/test_ldap.py
+++ b/modoboa/core/tests/test_ldap.py
@@ -2,8 +2,6 @@
 
 """Tests for core application."""
 
-from __future__ import unicode_literals
-
 from unittest import skipIf
 
 from django.test import override_settings
diff --git a/modoboa/core/tests/test_views.py b/modoboa/core/tests/test_views.py
index 498892c99..877f524ab 100644
--- a/modoboa/core/tests/test_views.py
+++ b/modoboa/core/tests/test_views.py
@@ -2,8 +2,6 @@
 
 """Core views test cases."""
 
-from __future__ import unicode_literals
-
 from testfixtures import compare
 
 from django import forms
diff --git a/modoboa/core/urls.py b/modoboa/core/urls.py
index 8b0fd2f95..5d4e69d15 100644
--- a/modoboa/core/urls.py
+++ b/modoboa/core/urls.py
@@ -2,8 +2,6 @@
 
 """Core urls."""
 
-from __future__ import unicode_literals
-
 from django.conf.urls import url
 
 from . import views
diff --git a/modoboa/core/utils.py b/modoboa/core/utils.py
index 8d992880a..d5ad42fe4 100644
--- a/modoboa/core/utils.py
+++ b/modoboa/core/utils.py
@@ -2,8 +2,6 @@
 
 """Utility functions."""
 
-from __future__ import unicode_literals
-
 from pkg_resources import parse_version
 
 from django.utils.translation import ugettext as _
diff --git a/modoboa/core/views/__init__.py b/modoboa/core/views/__init__.py
index 479f86c7f..c5aa51ea0 100644
--- a/modoboa/core/views/__init__.py
+++ b/modoboa/core/views/__init__.py
@@ -2,8 +2,6 @@
 
 """Core views."""
 
-from __future__ import unicode_literals
-
 from .admin import (
     check_top_notifications, information, logs, logs_page, parameters,
     viewsettings
diff --git a/modoboa/core/views/admin.py b/modoboa/core/views/admin.py
index d1ec82099..e85a30c8d 100644
--- a/modoboa/core/views/admin.py
+++ b/modoboa/core/views/admin.py
@@ -2,8 +2,6 @@
 
 """Views available to super administrators only."""
 
-from __future__ import unicode_literals
-
 from functools import reduce
 
 from django.contrib.auth.decorators import login_required, user_passes_test
diff --git a/modoboa/core/views/auth.py b/modoboa/core/views/auth.py
index 8945f7bf4..bd0e19c4f 100644
--- a/modoboa/core/views/auth.py
+++ b/modoboa/core/views/auth.py
@@ -2,8 +2,6 @@
 
 """Core authentication views."""
 
-from __future__ import unicode_literals
-
 import logging
 
 from django.contrib.auth import (
diff --git a/modoboa/core/views/base.py b/modoboa/core/views/base.py
index 32ed7651e..f907e80f2 100644
--- a/modoboa/core/views/base.py
+++ b/modoboa/core/views/base.py
@@ -2,8 +2,6 @@
 
 """Base core views."""
 
-from __future__ import unicode_literals
-
 from django.contrib.auth import mixins as auth_mixins
 from django.urls import reverse
 from django.utils.http import is_safe_url
diff --git a/modoboa/core/views/dashboard.py b/modoboa/core/views/dashboard.py
index 669bc424d..46901dac3 100644
--- a/modoboa/core/views/dashboard.py
+++ b/modoboa/core/views/dashboard.py
@@ -2,8 +2,6 @@
 
 """Core dashboard views."""
 
-from __future__ import unicode_literals
-
 import feedparser
 import requests
 from dateutil import parser
diff --git a/modoboa/core/views/user.py b/modoboa/core/views/user.py
index 22dea631b..c311bf778 100644
--- a/modoboa/core/views/user.py
+++ b/modoboa/core/views/user.py
@@ -2,8 +2,6 @@
 
 """Simple user views."""
 
-from __future__ import unicode_literals
-
 from django.contrib.auth.decorators import login_required, user_passes_test
 from django.shortcuts import render
 from django.template.loader import render_to_string
diff --git a/modoboa/dnstools/factories.py b/modoboa/dnstools/factories.py
index 4a0b86641..fb8a7710e 100644
--- a/modoboa/dnstools/factories.py
+++ b/modoboa/dnstools/factories.py
@@ -1,7 +1,5 @@
 """App related factories."""
 
-from __future__ import unicode_literals
-
 import factory
 
 from modoboa.admin import factories as admin_factories
diff --git a/modoboa/dnstools/lib.py b/modoboa/dnstools/lib.py
index e66b35283..1fd837ae1 100644
--- a/modoboa/dnstools/lib.py
+++ b/modoboa/dnstools/lib.py
@@ -1,7 +1,5 @@
 """dnstools library."""
 
-from __future__ import unicode_literals
-
 import ipaddress
 
 from django.utils.translation import ugettext as _
diff --git a/modoboa/dnstools/migrations/0001_initial.py b/modoboa/dnstools/migrations/0001_initial.py
index 6fd8e9891..a3624d8c7 100644
--- a/modoboa/dnstools/migrations/0001_initial.py
+++ b/modoboa/dnstools/migrations/0001_initial.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.11.16 on 2018-11-19 10:07
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import django.db.models.deletion
 import django.utils.timezone
diff --git a/modoboa/dnstools/models.py b/modoboa/dnstools/models.py
index 20e0a8d89..a2bd43a37 100644
--- a/modoboa/dnstools/models.py
+++ b/modoboa/dnstools/models.py
@@ -1,7 +1,5 @@
 """App related models."""
 
-from __future__ import unicode_literals
-
 import datetime
 
 from django.db import models
diff --git a/modoboa/ldapsync/lib.py b/modoboa/ldapsync/lib.py
index 89b371680..fd8a345c1 100644
--- a/modoboa/ldapsync/lib.py
+++ b/modoboa/ldapsync/lib.py
@@ -1,7 +1,5 @@
 """LDAP related functions."""
 
-from __future__ import unicode_literals
-
 import ldap
 import ldap.modlist as modlist
 
diff --git a/modoboa/ldapsync/tests.py b/modoboa/ldapsync/tests.py
index 448d28ae9..2e975a09b 100644
--- a/modoboa/ldapsync/tests.py
+++ b/modoboa/ldapsync/tests.py
@@ -1,7 +1,5 @@
 """LDAP sync. related tests."""
 
-from __future__ import unicode_literals
-
 from unittest import skipIf
 
 from django.utils import six
diff --git a/modoboa/lib/api_client.py b/modoboa/lib/api_client.py
index 70cf45d87..46d3f8ebf 100644
--- a/modoboa/lib/api_client.py
+++ b/modoboa/lib/api_client.py
@@ -2,8 +2,6 @@
 
 """A client for Modoboa's public API."""
 
-from __future__ import unicode_literals
-
 import os
 
 import pkg_resources
diff --git a/modoboa/lib/authbackends.py b/modoboa/lib/authbackends.py
index 9f8644726..e11980531 100644
--- a/modoboa/lib/authbackends.py
+++ b/modoboa/lib/authbackends.py
@@ -2,8 +2,6 @@
 
 """Custom authentication backends."""
 
-from __future__ import unicode_literals
-
 import smtplib
 
 from django.conf import settings
diff --git a/modoboa/lib/connections.py b/modoboa/lib/connections.py
index 5a194f674..1f7daa6bb 100644
--- a/modoboa/lib/connections.py
+++ b/modoboa/lib/connections.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 from modoboa.lib.cryptutils import decrypt
 
 
diff --git a/modoboa/lib/cryptutils.py b/modoboa/lib/cryptutils.py
index 41815a38f..4c41ab143 100644
--- a/modoboa/lib/cryptutils.py
+++ b/modoboa/lib/cryptutils.py
@@ -2,8 +2,6 @@
 
 """Crypto related utilities."""
 
-from __future__ import unicode_literals
-
 import base64
 
 from cryptography.fernet import Fernet
diff --git a/modoboa/lib/db_utils.py b/modoboa/lib/db_utils.py
index 3336ed1ac..248f0060d 100644
--- a/modoboa/lib/db_utils.py
+++ b/modoboa/lib/db_utils.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 from django.conf import settings
 from django.db import connection
 from django.utils.translation import ugettext as _
diff --git a/modoboa/lib/email_utils.py b/modoboa/lib/email_utils.py
index 3eb25b9f0..572f41cbb 100644
--- a/modoboa/lib/email_utils.py
+++ b/modoboa/lib/email_utils.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 import email
 import re
 import smtplib
diff --git a/modoboa/lib/exceptions.py b/modoboa/lib/exceptions.py
index 9a672e8ca..6ce42739e 100644
--- a/modoboa/lib/exceptions.py
+++ b/modoboa/lib/exceptions.py
@@ -6,8 +6,6 @@
 
 """
 
-from __future__ import unicode_literals
-
 from django.utils.translation import ugettext as _
 
 
diff --git a/modoboa/lib/fields.py b/modoboa/lib/fields.py
index 52f53cd72..afe75d845 100644
--- a/modoboa/lib/fields.py
+++ b/modoboa/lib/fields.py
@@ -2,8 +2,6 @@
 
 """Custom form fields."""
 
-from __future__ import unicode_literals
-
 from django import forms
 from django.utils.translation import ugettext_lazy
 
diff --git a/modoboa/lib/form_utils.py b/modoboa/lib/form_utils.py
index 937e0e8d9..87ea007f3 100644
--- a/modoboa/lib/form_utils.py
+++ b/modoboa/lib/form_utils.py
@@ -2,8 +2,6 @@
 
 """Form management utilities."""
 
-from __future__ import unicode_literals
-
 import abc
 import re
 from collections import OrderedDict
diff --git a/modoboa/lib/imap_utf7.py b/modoboa/lib/imap_utf7.py
index 34efc3778..95caa987b 100644
--- a/modoboa/lib/imap_utf7.py
+++ b/modoboa/lib/imap_utf7.py
@@ -51,8 +51,6 @@ Found here:
 http://svn.plone.org/svn/collective/mxmImapClient/trunk/imapUTF7.py
 
 """
-from __future__ import print_function, unicode_literals
-
 import codecs
 
 # encoding
diff --git a/modoboa/lib/ldap_utils.py b/modoboa/lib/ldap_utils.py
index c7ec9235d..35374c007 100644
--- a/modoboa/lib/ldap_utils.py
+++ b/modoboa/lib/ldap_utils.py
@@ -33,8 +33,6 @@ Extracted from `this blog
 
 """
 
-from __future__ import unicode_literals
-
 import ldap
 
 from django.conf import settings
diff --git a/modoboa/lib/listing.py b/modoboa/lib/listing.py
index 8237719fe..a66f85d1f 100644
--- a/modoboa/lib/listing.py
+++ b/modoboa/lib/listing.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 from django.core.paginator import EmptyPage, PageNotAnInteger, Paginator
 
 from modoboa.parameters import tools as param_tools
diff --git a/modoboa/lib/middleware.py b/modoboa/lib/middleware.py
index 2273e6b1e..4ed071de9 100644
--- a/modoboa/lib/middleware.py
+++ b/modoboa/lib/middleware.py
@@ -2,8 +2,6 @@
 
 """Custom middlewares."""
 
-from __future__ import unicode_literals
-
 from django.http import HttpResponseRedirect
 from django.utils.deprecation import MiddlewareMixin
 from django.utils.encoding import smart_text
diff --git a/modoboa/lib/migrations/0001_initial.py b/modoboa/lib/migrations/0001_initial.py
index 6f5cd6f93..c1f59bbb3 100644
--- a/modoboa/lib/migrations/0001_initial.py
+++ b/modoboa/lib/migrations/0001_initial.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 from django.conf import settings
 
diff --git a/modoboa/lib/migrations/0002_rename_parameters.py b/modoboa/lib/migrations/0002_rename_parameters.py
index da484142b..c7c85d519 100644
--- a/modoboa/lib/migrations/0002_rename_parameters.py
+++ b/modoboa/lib/migrations/0002_rename_parameters.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 APPLICATIONS = [
diff --git a/modoboa/lib/migrations/0003_rename_parameters.py b/modoboa/lib/migrations/0003_rename_parameters.py
index 642e5a5a8..193206bb9 100644
--- a/modoboa/lib/migrations/0003_rename_parameters.py
+++ b/modoboa/lib/migrations/0003_rename_parameters.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 APPS = (
diff --git a/modoboa/lib/migrations/0004_auto_20151114_1409.py b/modoboa/lib/migrations/0004_auto_20151114_1409.py
index e66d38167..fe5fa0d61 100644
--- a/modoboa/lib/migrations/0004_auto_20151114_1409.py
+++ b/modoboa/lib/migrations/0004_auto_20151114_1409.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 
diff --git a/modoboa/lib/migrations/0005_auto_20160416_1449.py b/modoboa/lib/migrations/0005_auto_20160416_1449.py
index 6c594dec3..1a10f9519 100644
--- a/modoboa/lib/migrations/0005_auto_20160416_1449.py
+++ b/modoboa/lib/migrations/0005_auto_20160416_1449.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import migrations
 
 
diff --git a/modoboa/lib/migrations/0006_auto_20161104_2206.py b/modoboa/lib/migrations/0006_auto_20161104_2206.py
index 105af9718..b937f2131 100644
--- a/modoboa/lib/migrations/0006_auto_20161104_2206.py
+++ b/modoboa/lib/migrations/0006_auto_20161104_2206.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.9.5 on 2016-11-04 21:06
-from __future__ import unicode_literals
-
 from django.db import migrations
 
 
diff --git a/modoboa/lib/migrations/__init__.py b/modoboa/lib/migrations/__init__.py
index baffc4882..e69de29bb 100644
--- a/modoboa/lib/migrations/__init__.py
+++ b/modoboa/lib/migrations/__init__.py
@@ -1 +0,0 @@
-from __future__ import unicode_literals
diff --git a/modoboa/lib/paginator.py b/modoboa/lib/paginator.py
index 9006ded56..d3e3a4690 100644
--- a/modoboa/lib/paginator.py
+++ b/modoboa/lib/paginator.py
@@ -4,9 +4,6 @@
 Custom pagination tools.
 """
 
-from __future__ import unicode_literals
-
-
 class Page(object):
 
     """Class to represent a page."""
diff --git a/modoboa/lib/permissions.py b/modoboa/lib/permissions.py
index b1705bd77..292fd37fe 100644
--- a/modoboa/lib/permissions.py
+++ b/modoboa/lib/permissions.py
@@ -2,8 +2,6 @@
 
 """Object level permissions."""
 
-from __future__ import unicode_literals
-
 from django.contrib.auth.models import Group, Permission
 from django.contrib.contenttypes.models import ContentType
 
diff --git a/modoboa/lib/signals.py b/modoboa/lib/signals.py
index 46c4795b1..692e4d102 100644
--- a/modoboa/lib/signals.py
+++ b/modoboa/lib/signals.py
@@ -2,8 +2,6 @@
 
 """Custom signals."""
 
-from __future__ import unicode_literals
-
 from threading import local
 
 _local_store = local()
diff --git a/modoboa/lib/singleton.py b/modoboa/lib/singleton.py
index 2033d7c6e..db4ab223a 100644
--- a/modoboa/lib/singleton.py
+++ b/modoboa/lib/singleton.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 
 # works in Python 2 & 3
 class _Singleton(type):
diff --git a/modoboa/lib/sysutils.py b/modoboa/lib/sysutils.py
index eb0b8c92f..fec12846f 100644
--- a/modoboa/lib/sysutils.py
+++ b/modoboa/lib/sysutils.py
@@ -5,8 +5,6 @@ This module extra functions/shortcuts to communicate with the system
 (executing commands, etc.)
 """
 
-from __future__ import unicode_literals
-
 import inspect
 import os
 import re
diff --git a/modoboa/lib/templatetags/form_tags.py b/modoboa/lib/templatetags/form_tags.py
index 796fce0be..49d823ff3 100644
--- a/modoboa/lib/templatetags/form_tags.py
+++ b/modoboa/lib/templatetags/form_tags.py
@@ -4,8 +4,6 @@
 Form rendering tags.
 """
 
-from __future__ import unicode_literals
-
 from django import forms, template
 from django.template.loader import render_to_string
 from django.utils.encoding import smart_text
diff --git a/modoboa/lib/templatetags/lib_tags.py b/modoboa/lib/templatetags/lib_tags.py
index 41a086d31..4682fea23 100644
--- a/modoboa/lib/templatetags/lib_tags.py
+++ b/modoboa/lib/templatetags/lib_tags.py
@@ -2,8 +2,6 @@
 
 """Custom template tags."""
 
-from __future__ import unicode_literals
-
 from datetime import datetime
 
 from django import template
diff --git a/modoboa/lib/test_utils.py b/modoboa/lib/test_utils.py
index 51b4be356..7b0b9deaf 100644
--- a/modoboa/lib/test_utils.py
+++ b/modoboa/lib/test_utils.py
@@ -2,8 +2,6 @@
 
 """Tools for top level testing (ie. when ran by Travis)."""
 
-from __future__ import unicode_literals
-
 import os
 import shutil
 import tempfile
diff --git a/modoboa/lib/tests/__init__.py b/modoboa/lib/tests/__init__.py
index 7eb668515..254c1f2c4 100644
--- a/modoboa/lib/tests/__init__.py
+++ b/modoboa/lib/tests/__init__.py
@@ -2,8 +2,6 @@
 
 """Testing utilities."""
 
-from __future__ import unicode_literals
-
 import socket
 
 from django.core import management
diff --git a/modoboa/lib/tests/test_cryptutils.py b/modoboa/lib/tests/test_cryptutils.py
index 4c3f852d9..0bac68a92 100644
--- a/modoboa/lib/tests/test_cryptutils.py
+++ b/modoboa/lib/tests/test_cryptutils.py
@@ -2,8 +2,6 @@
 
 """Tests for crypto utility functions."""
 
-from __future__ import unicode_literals
-
 from django.test import SimpleTestCase
 from django.test.utils import override_settings
 
diff --git a/modoboa/lib/tests/test_email_utils.py b/modoboa/lib/tests/test_email_utils.py
index 6b2c8bbc4..12361dc61 100644
--- a/modoboa/lib/tests/test_email_utils.py
+++ b/modoboa/lib/tests/test_email_utils.py
@@ -2,8 +2,6 @@
 
 """Tests for email_utils."""
 
-from __future__ import unicode_literals
-
 import os
 
 from django.test import SimpleTestCase
diff --git a/modoboa/lib/tests/test_u2u_decode.py b/modoboa/lib/tests/test_u2u_decode.py
index 9c64cae46..e84aa498c 100644
--- a/modoboa/lib/tests/test_u2u_decode.py
+++ b/modoboa/lib/tests/test_u2u_decode.py
@@ -2,8 +2,6 @@
 
 """Tests for u2u_decode."""
 
-from __future__ import unicode_literals
-
 from django.test import TestCase
 
 from .. import u2u_decode
diff --git a/modoboa/lib/u2u_decode.py b/modoboa/lib/u2u_decode.py
index 5d9367557..cd8403223 100644
--- a/modoboa/lib/u2u_decode.py
+++ b/modoboa/lib/u2u_decode.py
@@ -7,8 +7,6 @@ A stupid (and not accurate) answer to https://bugs.python.org/issue1079.
 
 """
 
-from __future__ import unicode_literals
-
 import re
 from email.header import decode_header, make_header
 from email.utils import parseaddr
diff --git a/modoboa/lib/validators.py b/modoboa/lib/validators.py
index 80bd95ca2..5699fa9ed 100644
--- a/modoboa/lib/validators.py
+++ b/modoboa/lib/validators.py
@@ -2,8 +2,6 @@
 
 """Field validators."""
 
-from __future__ import unicode_literals
-
 import re
 
 from django.core.exceptions import ValidationError
diff --git a/modoboa/lib/web_utils.py b/modoboa/lib/web_utils.py
index de54f63df..0b0ca4861 100644
--- a/modoboa/lib/web_utils.py
+++ b/modoboa/lib/web_utils.py
@@ -4,8 +4,6 @@
 This module contains extra functions/shortcuts used to render HTML.
 """
 
-from __future__ import unicode_literals
-
 import json
 import re
 import sys
diff --git a/modoboa/limits/__init__.py b/modoboa/limits/__init__.py
index 01758a791..1ea55179c 100644
--- a/modoboa/limits/__init__.py
+++ b/modoboa/limits/__init__.py
@@ -1,5 +1,3 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 default_app_config = "modoboa.limits.apps.LimitsConfig"
diff --git a/modoboa/limits/app_settings.py b/modoboa/limits/app_settings.py
index 070a38f23..e34c8a9a1 100644
--- a/modoboa/limits/app_settings.py
+++ b/modoboa/limits/app_settings.py
@@ -2,8 +2,6 @@
 
 """Custom settings."""
 
-from __future__ import unicode_literals
-
 from django import forms
 from django.utils.translation import ugettext_lazy as _
 
diff --git a/modoboa/limits/apps.py b/modoboa/limits/apps.py
index 7f066caf0..f578d63a2 100644
--- a/modoboa/limits/apps.py
+++ b/modoboa/limits/apps.py
@@ -2,8 +2,6 @@
 
 """App config for limits."""
 
-from __future__ import unicode_literals
-
 from django.apps import AppConfig
 from django.utils.translation import ugettext as _
 
diff --git a/modoboa/limits/constants.py b/modoboa/limits/constants.py
index 570d961aa..e6cc2be03 100644
--- a/modoboa/limits/constants.py
+++ b/modoboa/limits/constants.py
@@ -2,8 +2,6 @@
 
 """Modoboa limits constants."""
 
-from __future__ import unicode_literals
-
 import collections
 
 from django.utils.translation import ugettext_lazy as _
diff --git a/modoboa/limits/forms.py b/modoboa/limits/forms.py
index 7b91c377d..3c1a4fe50 100644
--- a/modoboa/limits/forms.py
+++ b/modoboa/limits/forms.py
@@ -2,8 +2,6 @@
 
 """Custom forms."""
 
-from __future__ import unicode_literals
-
 from django import forms
 from django.utils.translation import ugettext as _
 
diff --git a/modoboa/limits/handlers.py b/modoboa/limits/handlers.py
index 57309b405..05d419b09 100644
--- a/modoboa/limits/handlers.py
+++ b/modoboa/limits/handlers.py
@@ -2,8 +2,6 @@
 
 """Django signal handlers for limits."""
 
-from __future__ import unicode_literals
-
 from django.contrib.contenttypes.models import ContentType
 from django.db.models import signals
 from django.dispatch import receiver
diff --git a/modoboa/limits/lib.py b/modoboa/limits/lib.py
index 68dcb734a..c4f7c50ed 100644
--- a/modoboa/limits/lib.py
+++ b/modoboa/limits/lib.py
@@ -6,8 +6,6 @@
 
 """
 
-from __future__ import unicode_literals
-
 from django.utils.translation import ugettext as _
 
 from modoboa.lib.exceptions import ModoboaException
diff --git a/modoboa/limits/migrations/0001_initial.py b/modoboa/limits/migrations/0001_initial.py
index 2c1d96230..a7c57de3a 100644
--- a/modoboa/limits/migrations/0001_initial.py
+++ b/modoboa/limits/migrations/0001_initial.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 from django.conf import settings
 
diff --git a/modoboa/limits/migrations/0002_auto_20151114_1518.py b/modoboa/limits/migrations/0002_auto_20151114_1518.py
index a6ed7714f..9da2249d9 100644
--- a/modoboa/limits/migrations/0002_auto_20151114_1518.py
+++ b/modoboa/limits/migrations/0002_auto_20151114_1518.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 
diff --git a/modoboa/limits/migrations/0003_auto_20160413_1046.py b/modoboa/limits/migrations/0003_auto_20160413_1046.py
index 625a90568..188780bd7 100644
--- a/modoboa/limits/migrations/0003_auto_20160413_1046.py
+++ b/modoboa/limits/migrations/0003_auto_20160413_1046.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 from django.conf import settings
 
diff --git a/modoboa/limits/migrations/0004_auto_20160413_1312.py b/modoboa/limits/migrations/0004_auto_20160413_1312.py
index fe085dd35..71850e7ba 100644
--- a/modoboa/limits/migrations/0004_auto_20160413_1312.py
+++ b/modoboa/limits/migrations/0004_auto_20160413_1312.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/limits/migrations/0005_auto_20160415_1654.py b/modoboa/limits/migrations/0005_auto_20160415_1654.py
index 9b05b9f08..5eae6f8ff 100644
--- a/modoboa/limits/migrations/0005_auto_20160415_1654.py
+++ b/modoboa/limits/migrations/0005_auto_20160415_1654.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import modoboa.limits.models
 
diff --git a/modoboa/limits/migrations/0006_auto_20170216_1112.py b/modoboa/limits/migrations/0006_auto_20170216_1112.py
index d195d54b1..0ce9ea60c 100644
--- a/modoboa/limits/migrations/0006_auto_20170216_1112.py
+++ b/modoboa/limits/migrations/0006_auto_20170216_1112.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.10.5 on 2017-02-16 10:12
-from __future__ import unicode_literals
-
 from django.db import migrations
 
 
diff --git a/modoboa/limits/migrations/__init__.py b/modoboa/limits/migrations/__init__.py
index baffc4882..e69de29bb 100644
--- a/modoboa/limits/migrations/__init__.py
+++ b/modoboa/limits/migrations/__init__.py
@@ -1 +0,0 @@
-from __future__ import unicode_literals
diff --git a/modoboa/limits/models.py b/modoboa/limits/models.py
index ce62d9bfc..638229a2b 100644
--- a/modoboa/limits/models.py
+++ b/modoboa/limits/models.py
@@ -2,8 +2,6 @@
 
 """Models for the limits extensions."""
 
-from __future__ import unicode_literals
-
 from django.conf import settings
 from django.db import models
 from django.utils.encoding import python_2_unicode_compatible
diff --git a/modoboa/limits/serializers.py b/modoboa/limits/serializers.py
index 9fa0cbd00..dcabc1e9c 100644
--- a/modoboa/limits/serializers.py
+++ b/modoboa/limits/serializers.py
@@ -2,8 +2,6 @@
 
 """Limits serializers."""
 
-from __future__ import unicode_literals
-
 from rest_framework import serializers
 
 from . import lib
diff --git a/modoboa/limits/tests/test_api.py b/modoboa/limits/tests/test_api.py
index 890c05556..252a4205a 100644
--- a/modoboa/limits/tests/test_api.py
+++ b/modoboa/limits/tests/test_api.py
@@ -2,8 +2,6 @@
 
 """Test cases for the limits extension."""
 
-from __future__ import unicode_literals
-
 from testfixtures import compare
 
 from django.urls import reverse
diff --git a/modoboa/limits/tests/test_domain_limits.py b/modoboa/limits/tests/test_domain_limits.py
index 9442cda99..052d5534b 100644
--- a/modoboa/limits/tests/test_domain_limits.py
+++ b/modoboa/limits/tests/test_domain_limits.py
@@ -2,8 +2,6 @@
 
 """Test cases for the limits extension."""
 
-from __future__ import unicode_literals
-
 from django.urls import reverse
 
 from modoboa.admin import factories as admin_factories
diff --git a/modoboa/limits/tests/test_import.py b/modoboa/limits/tests/test_import.py
index 109021f45..4f6eb3a3b 100644
--- a/modoboa/limits/tests/test_import.py
+++ b/modoboa/limits/tests/test_import.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 from django.core.files.base import ContentFile
 from django.urls import reverse
 
diff --git a/modoboa/limits/tests/test_user_limits.py b/modoboa/limits/tests/test_user_limits.py
index 41bb40706..9915e4abe 100644
--- a/modoboa/limits/tests/test_user_limits.py
+++ b/modoboa/limits/tests/test_user_limits.py
@@ -2,8 +2,6 @@
 
 """Test cases for the limits extension."""
 
-from __future__ import unicode_literals
-
 from django.urls import reverse
 
 from modoboa.admin.factories import populate_database
diff --git a/modoboa/limits/urls_api.py b/modoboa/limits/urls_api.py
index 39c2e4f03..a7f6c1753 100644
--- a/modoboa/limits/urls_api.py
+++ b/modoboa/limits/urls_api.py
@@ -2,8 +2,6 @@
 
 """Limits API urls."""
 
-from __future__ import unicode_literals
-
 from rest_framework import routers
 
 from . import viewsets
diff --git a/modoboa/limits/utils.py b/modoboa/limits/utils.py
index ebbb11972..cf6c47bbf 100644
--- a/modoboa/limits/utils.py
+++ b/modoboa/limits/utils.py
@@ -2,8 +2,6 @@
 
 """Modoboa limits utilities."""
 
-from __future__ import unicode_literals
-
 from . import constants
 
 
diff --git a/modoboa/limits/viewsets.py b/modoboa/limits/viewsets.py
index 7cb8b3e55..76e4f5000 100644
--- a/modoboa/limits/viewsets.py
+++ b/modoboa/limits/viewsets.py
@@ -2,8 +2,6 @@
 
 """Limits API."""
 
-from __future__ import unicode_literals
-
 from django.contrib.contenttypes.models import ContentType
 
 from rest_framework import mixins, viewsets
diff --git a/modoboa/parameters/apps.py b/modoboa/parameters/apps.py
index f60d64f47..407aac5be 100644
--- a/modoboa/parameters/apps.py
+++ b/modoboa/parameters/apps.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 from django.apps import AppConfig
 
 
diff --git a/modoboa/parameters/forms.py b/modoboa/parameters/forms.py
index 19243c7b0..736253a5c 100644
--- a/modoboa/parameters/forms.py
+++ b/modoboa/parameters/forms.py
@@ -2,8 +2,6 @@
 
 """Parameters forms."""
 
-from __future__ import unicode_literals
-
 from django import forms
 
 from modoboa.lib import db_utils, form_utils
diff --git a/modoboa/parameters/tools.py b/modoboa/parameters/tools.py
index 5187ec0a5..58df27d47 100644
--- a/modoboa/parameters/tools.py
+++ b/modoboa/parameters/tools.py
@@ -2,8 +2,6 @@
 
 """Parameters management."""
 
-from __future__ import unicode_literals
-
 import copy
 
 from modoboa.lib import exceptions, form_utils, signals
diff --git a/modoboa/relaydomains/__init__.py b/modoboa/relaydomains/__init__.py
index 05dc26897..2e61ad8ae 100644
--- a/modoboa/relaydomains/__init__.py
+++ b/modoboa/relaydomains/__init__.py
@@ -1,5 +1,3 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 default_app_config = "modoboa.relaydomains.apps.RelayDomainsConfig"
diff --git a/modoboa/relaydomains/apps.py b/modoboa/relaydomains/apps.py
index cfdb726b3..ab56d701b 100644
--- a/modoboa/relaydomains/apps.py
+++ b/modoboa/relaydomains/apps.py
@@ -2,8 +2,6 @@
 
 """AppConfig for relaydomains."""
 
-from __future__ import unicode_literals
-
 from django.apps import AppConfig
 
 
diff --git a/modoboa/relaydomains/forms.py b/modoboa/relaydomains/forms.py
index f9b40e6d6..8bb3ba159 100644
--- a/modoboa/relaydomains/forms.py
+++ b/modoboa/relaydomains/forms.py
@@ -2,8 +2,6 @@
 
 """Postfix relay domains extension forms."""
 
-from __future__ import unicode_literals
-
 from django.db.models.signals import pre_save, post_save
 
 from modoboa.lib.form_utils import WizardStep
diff --git a/modoboa/relaydomains/handlers.py b/modoboa/relaydomains/handlers.py
index b06effa28..ec38b6b93 100644
--- a/modoboa/relaydomains/handlers.py
+++ b/modoboa/relaydomains/handlers.py
@@ -2,8 +2,6 @@
 
 """Django signal handlers for relaydomains."""
 
-from __future__ import unicode_literals
-
 from django.db.models import signals
 from django.dispatch import receiver
 from django.utils.translation import ugettext as _
diff --git a/modoboa/relaydomains/lib.py b/modoboa/relaydomains/lib.py
index bcebef70b..fedd51616 100644
--- a/modoboa/relaydomains/lib.py
+++ b/modoboa/relaydomains/lib.py
@@ -2,8 +2,6 @@
 
 """Internal library."""
 
-from __future__ import unicode_literals
-
 from django.utils.translation import ugettext as _
 
 from modoboa.admin import models as admin_models
diff --git a/modoboa/relaydomains/migrations/0001_initial.py b/modoboa/relaydomains/migrations/0001_initial.py
index 84cf66c6a..b233b67d9 100644
--- a/modoboa/relaydomains/migrations/0001_initial.py
+++ b/modoboa/relaydomains/migrations/0001_initial.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 
diff --git a/modoboa/relaydomains/migrations/0002_migrate_from_modoboa_admin_relaydomains.py b/modoboa/relaydomains/migrations/0002_migrate_from_modoboa_admin_relaydomains.py
index e100533fc..aa32af599 100644
--- a/modoboa/relaydomains/migrations/0002_migrate_from_modoboa_admin_relaydomains.py
+++ b/modoboa/relaydomains/migrations/0002_migrate_from_modoboa_admin_relaydomains.py
@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 
diff --git a/modoboa/relaydomains/migrations/0003_auto_20170116_1508.py b/modoboa/relaydomains/migrations/0003_auto_20170116_1508.py
index 19c94ce5b..ab092c3ff 100644
--- a/modoboa/relaydomains/migrations/0003_auto_20170116_1508.py
+++ b/modoboa/relaydomains/migrations/0003_auto_20170116_1508.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.9.12 on 2017-01-16 14:08
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/relaydomains/migrations/0004_auto_20161105_1424.py b/modoboa/relaydomains/migrations/0004_auto_20161105_1424.py
index 7c0320a81..b0700c8a6 100644
--- a/modoboa/relaydomains/migrations/0004_auto_20161105_1424.py
+++ b/modoboa/relaydomains/migrations/0004_auto_20161105_1424.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.9.5 on 2016-11-05 13:24
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import django.utils.timezone
 
diff --git a/modoboa/relaydomains/migrations/0005_auto_20161105_1426.py b/modoboa/relaydomains/migrations/0005_auto_20161105_1426.py
index a056781d5..8e1d65143 100644
--- a/modoboa/relaydomains/migrations/0005_auto_20161105_1426.py
+++ b/modoboa/relaydomains/migrations/0005_auto_20161105_1426.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.9.5 on 2016-11-05 13:26
-from __future__ import unicode_literals
-
 from django.db import migrations
 
 
diff --git a/modoboa/relaydomains/migrations/0006_auto_20170215_0948.py b/modoboa/relaydomains/migrations/0006_auto_20170215_0948.py
index 6f0ed989d..76b34c521 100644
--- a/modoboa/relaydomains/migrations/0006_auto_20170215_0948.py
+++ b/modoboa/relaydomains/migrations/0006_auto_20170215_0948.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.10.5 on 2017-02-15 08:48
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import django.utils.timezone
 
diff --git a/modoboa/relaydomains/migrations/0007_recipientaccess.py b/modoboa/relaydomains/migrations/0007_recipientaccess.py
index 4c86b5099..99c3324e5 100644
--- a/modoboa/relaydomains/migrations/0007_recipientaccess.py
+++ b/modoboa/relaydomains/migrations/0007_recipientaccess.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.10.7 on 2017-11-24 14:06
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/relaydomains/migrations/0008_auto_20171123_1653.py b/modoboa/relaydomains/migrations/0008_auto_20171123_1653.py
index e92b8e3af..a4f177483 100644
--- a/modoboa/relaydomains/migrations/0008_auto_20171123_1653.py
+++ b/modoboa/relaydomains/migrations/0008_auto_20171123_1653.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.10.7 on 2017-11-23 15:53
-from __future__ import unicode_literals
-
 from django.db import migrations
 
 
diff --git a/modoboa/relaydomains/migrations/0009_auto_20171124_1508.py b/modoboa/relaydomains/migrations/0009_auto_20171124_1508.py
index 2c4a0f9c7..d8aa4268d 100644
--- a/modoboa/relaydomains/migrations/0009_auto_20171124_1508.py
+++ b/modoboa/relaydomains/migrations/0009_auto_20171124_1508.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.10.7 on 2017-11-24 14:08
-from __future__ import unicode_literals
-
 from django.db import migrations
 
 
diff --git a/modoboa/relaydomains/migrations/__init__.py b/modoboa/relaydomains/migrations/__init__.py
index baffc4882..e69de29bb 100644
--- a/modoboa/relaydomains/migrations/__init__.py
+++ b/modoboa/relaydomains/migrations/__init__.py
@@ -1 +0,0 @@
-from __future__ import unicode_literals
diff --git a/modoboa/relaydomains/models.py b/modoboa/relaydomains/models.py
index 5e3700c78..0adc20c42 100644
--- a/modoboa/relaydomains/models.py
+++ b/modoboa/relaydomains/models.py
@@ -2,8 +2,6 @@
 
 """Relay domain related models."""
 
-from __future__ import unicode_literals
-
 from django.db import models
 
 
diff --git a/modoboa/relaydomains/postfix_maps.py b/modoboa/relaydomains/postfix_maps.py
index 77c5904e0..bbb3d0c63 100644
--- a/modoboa/relaydomains/postfix_maps.py
+++ b/modoboa/relaydomains/postfix_maps.py
@@ -2,9 +2,6 @@
 
 """Map file definitions for postfix."""
 
-from __future__ import unicode_literals
-
-
 class RelayDomainsMap(object):
 
     """Map file to list all relay domains."""
diff --git a/modoboa/relaydomains/serializers.py b/modoboa/relaydomains/serializers.py
index 8887f2714..604052ad3 100644
--- a/modoboa/relaydomains/serializers.py
+++ b/modoboa/relaydomains/serializers.py
@@ -2,8 +2,6 @@
 
 """RelayDomain serializers."""
 
-from __future__ import unicode_literals
-
 import json
 
 from django.utils.translation import ugettext as _
diff --git a/modoboa/relaydomains/tests.py b/modoboa/relaydomains/tests.py
index ca828e5ce..ddc3d6169 100644
--- a/modoboa/relaydomains/tests.py
+++ b/modoboa/relaydomains/tests.py
@@ -2,8 +2,6 @@
 
 """relaydomains unit tests."""
 
-from __future__ import unicode_literals
-
 import json
 
 from django.core.files.base import ContentFile
diff --git a/modoboa/relaydomains/transport.py b/modoboa/relaydomains/transport.py
index 641b66897..4946bb279 100644
--- a/modoboa/relaydomains/transport.py
+++ b/modoboa/relaydomains/transport.py
@@ -2,8 +2,6 @@
 
 """Transport backend definition."""
 
-from __future__ import unicode_literals
-
 from django.utils.translation import ugettext_lazy as _
 
 from modoboa.transport import backends
diff --git a/modoboa/relaydomains/urls_api.py b/modoboa/relaydomains/urls_api.py
index 275a160dc..78e81cfc2 100644
--- a/modoboa/relaydomains/urls_api.py
+++ b/modoboa/relaydomains/urls_api.py
@@ -2,8 +2,6 @@
 
 """Transport API urls."""
 
-from __future__ import unicode_literals
-
 from rest_framework import routers
 
 from . import viewsets
diff --git a/modoboa/relaydomains/viewsets.py b/modoboa/relaydomains/viewsets.py
index 8f75e266b..183818339 100644
--- a/modoboa/relaydomains/viewsets.py
+++ b/modoboa/relaydomains/viewsets.py
@@ -2,8 +2,6 @@
 
 """RelayDomain viewsets."""
 
-from __future__ import unicode_literals
-
 from rest_framework import viewsets
 from rest_framework.permissions import DjangoModelPermissions, IsAuthenticated
 
diff --git a/modoboa/test_settings.py b/modoboa/test_settings.py
index 535b8c3c1..cd41389b7 100644
--- a/modoboa/test_settings.py
+++ b/modoboa/test_settings.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 import os
 
 # Database
diff --git a/modoboa/transport/__init__.py b/modoboa/transport/__init__.py
index 96b626725..63503991a 100644
--- a/modoboa/transport/__init__.py
+++ b/modoboa/transport/__init__.py
@@ -1,5 +1,3 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 default_app_config = "modoboa.transport.apps.TransportConfig"
diff --git a/modoboa/transport/apps.py b/modoboa/transport/apps.py
index 7d27b0001..55851bb67 100644
--- a/modoboa/transport/apps.py
+++ b/modoboa/transport/apps.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 from django.apps import AppConfig
 
 
diff --git a/modoboa/transport/backends.py b/modoboa/transport/backends.py
index dc2ae5500..29bd6d4bb 100644
--- a/modoboa/transport/backends.py
+++ b/modoboa/transport/backends.py
@@ -2,8 +2,6 @@
 
 """Transport backend."""
 
-from __future__ import unicode_literals
-
 from django import forms
 from django.core import validators
 from django.utils.translation import ugettext_lazy as _
diff --git a/modoboa/transport/constants.py b/modoboa/transport/constants.py
index b1786c081..87286d302 100644
--- a/modoboa/transport/constants.py
+++ b/modoboa/transport/constants.py
@@ -2,8 +2,6 @@
 
 """Transport constants."""
 
-from __future__ import unicode_literals
-
 PERMISSIONS = {
 
 }
diff --git a/modoboa/transport/factories.py b/modoboa/transport/factories.py
index 7e08e0b34..547fddad8 100644
--- a/modoboa/transport/factories.py
+++ b/modoboa/transport/factories.py
@@ -2,8 +2,6 @@
 
 """Transport factories."""
 
-from __future__ import unicode_literals
-
 import factory
 
 from . import models
diff --git a/modoboa/transport/forms.py b/modoboa/transport/forms.py
index 9309e0413..dd077b67f 100644
--- a/modoboa/transport/forms.py
+++ b/modoboa/transport/forms.py
@@ -2,8 +2,6 @@
 
 """Transport forms."""
 
-from __future__ import unicode_literals
-
 from django import forms
 
 from . import backends, models
diff --git a/modoboa/transport/handlers.py b/modoboa/transport/handlers.py
index 455b1030b..9d52d24d9 100644
--- a/modoboa/transport/handlers.py
+++ b/modoboa/transport/handlers.py
@@ -2,8 +2,6 @@
 
 """Transport handlers."""
 
-from __future__ import unicode_literals
-
 from django.db.models import signals
 from django.dispatch import receiver
 
diff --git a/modoboa/transport/migrations/0001_initial.py b/modoboa/transport/migrations/0001_initial.py
index 771b6a1ad..201f92cb4 100644
--- a/modoboa/transport/migrations/0001_initial.py
+++ b/modoboa/transport/migrations/0001_initial.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.10.7 on 2017-11-24 11:16
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 import jsonfield.fields
diff --git a/modoboa/transport/migrations/0002_auto_20180928_1520.py b/modoboa/transport/migrations/0002_auto_20180928_1520.py
index af5a49641..b8e7d31ca 100644
--- a/modoboa/transport/migrations/0002_auto_20180928_1520.py
+++ b/modoboa/transport/migrations/0002_auto_20180928_1520.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by Django 1.11.15 on 2018-09-28 13:20
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/transport/models.py b/modoboa/transport/models.py
index 0db5e59cf..fb3fee181 100644
--- a/modoboa/transport/models.py
+++ b/modoboa/transport/models.py
@@ -2,8 +2,6 @@
 
 """Transport models."""
 
-from __future__ import unicode_literals
-
 import jsonfield
 from reversion import revisions as reversion
 
diff --git a/modoboa/transport/postfix_maps.py b/modoboa/transport/postfix_maps.py
index a756fd57d..a526f38b3 100644
--- a/modoboa/transport/postfix_maps.py
+++ b/modoboa/transport/postfix_maps.py
@@ -2,9 +2,6 @@
 
 """Map file definitions for postfix."""
 
-from __future__ import unicode_literals
-
-
 class TransportMap(object):
     """A transport map."""
 
diff --git a/modoboa/urls.py b/modoboa/urls.py
index e8fe24b79..c6a771996 100644
--- a/modoboa/urls.py
+++ b/modoboa/urls.py
@@ -1,7 +1,5 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
-
 from functools import reduce
 
 from ckeditor_uploader import views as cku_views
diff --git a/modoboa/urls_api.py b/modoboa/urls_api.py
index ea1770cda..4df5320b1 100644
--- a/modoboa/urls_api.py
+++ b/modoboa/urls_api.py
@@ -2,8 +2,6 @@
 
 """External API urls."""
 
-from __future__ import unicode_literals
-
 from django.conf.urls import include, url
 
 from modoboa.core.extensions import exts_pool
diff --git a/tests.py b/tests.py
index 5177a3ec3..2fac9cd9b 100644
--- a/tests.py
+++ b/tests.py
@@ -1,5 +1,4 @@
 # coding: utf-8
-from __future__ import unicode_literals
 
 import os
 import tempfile