diff --git a/modoboa/extensions/admin/templatetags/admin_tags.py b/modoboa/extensions/admin/templatetags/admin_tags.py
index 24290feef..d05b8ad9c 100644
--- a/modoboa/extensions/admin/templatetags/admin_tags.py
+++ b/modoboa/extensions/admin/templatetags/admin_tags.py
@@ -147,7 +147,8 @@ def domain_actions(user, domain):
     if domain.__class__.__name__ == 'Domain':
         actions = [
             {"name": "listidentities",
-             "url": reverse("admin:identity_list") + "#list/?searchquery=@%s" % domain.name,
+             "url": "{0}#list/?searchquery=@{1}".format(
+                 reverse("admin:identity_list"), domain.name),
              "title": _("View the domain's identities"),
              "img": "fa fa-user"}
         ]
@@ -277,5 +278,3 @@ def get_extra_admin_content(user, target, currentpage):
         "ExtraAdminContent", user, target, currentpage
     )
     return "".join(res)
-
-
diff --git a/modoboa/extensions/admin/tests/account.py b/modoboa/extensions/admin/tests/account.py
index 12b16fee8..6881056a4 100644
--- a/modoboa/extensions/admin/tests/account.py
+++ b/modoboa/extensions/admin/tests/account.py
@@ -1,10 +1,11 @@
 from django.core.urlresolvers import reverse
+
 from modoboa.core.models import User
-from modoboa.lib.tests import ModoTestCase
+from modoboa.extensions.admin import factories
 from modoboa.extensions.admin.models import (
     Domain, Mailbox
 )
-from modoboa.extensions.admin import factories
+from modoboa.lib.tests import ModoTestCase
 
 
 class AccountTestCase(ModoTestCase):
@@ -62,10 +63,14 @@ class AccountTestCase(ModoTestCase):
 
     def test_set_nul_quota_as_domainadmin(self):
         self.clt.logout()
-        self.assertTrue(self.clt.login(username="admin@test.com", password="toto"))
+        self.assertTrue(
+            self.clt.login(username="admin@test.com", password="toto")
+        )
         self._set_quota("user@test.com", 0, 400)
         self.clt.logout()
-        self.assertTrue(self.clt.login(username="admin@test2.com", password="toto"))
+        self.assertTrue(
+            self.clt.login(username="admin@test2.com", password="toto")
+        )
         self._set_quota("user@test2.com", 0)
 
 
@@ -119,8 +124,9 @@ class PermissionsTestCase(ModoTestCase):
 
     def test_self_modif(self):
         self.clt.logout()
-        self.assertEqual(self.clt.login(username="admin@test.com", password="toto"),
-                         True)
+        self.assertTrue(
+            self.clt.login(username="admin@test.com", password="toto")
+        )
         admin = User.objects.get(username="admin@test.com")
         values = dict(
             username="admin@test.com", first_name="Admin",
@@ -132,7 +138,7 @@ class PermissionsTestCase(ModoTestCase):
             values
         )
         self.assertEqual(admin.group, "DomainAdmins")
-        self.assertEqual(admin.can_access(Domain.objects.get(name="test.com")), True)
+        self.assertTrue(admin.can_access(Domain.objects.get(name="test.com")))
 
         values["role"] = "SuperAdmins"
         self.ajax_post(
diff --git a/modoboa/extensions/admin/tests/alias.py b/modoboa/extensions/admin/tests/alias.py
index 5dbac1a8d..e470b8d49 100644
--- a/modoboa/extensions/admin/tests/alias.py
+++ b/modoboa/extensions/admin/tests/alias.py
@@ -1,10 +1,11 @@
 from django.core.urlresolvers import reverse
+
 from modoboa.core.models import User
-from modoboa.lib.tests import ModoTestCase
+from modoboa.extensions.admin import factories
 from modoboa.extensions.admin.models import (
     Alias
 )
-from modoboa.extensions.admin import factories
+from modoboa.lib.tests import ModoTestCase
 
 
 class AliasTestCase(ModoTestCase):
@@ -80,8 +81,8 @@ class AliasTestCase(ModoTestCase):
         self.assertEqual(fwd.get_recipients_count(), 1)
 
         self.ajax_post(
-            reverse("admin:alias_delete") + "?selection=%d" \
-                % fwd.id, {}
+            reverse("admin:alias_delete") + "?selection=%d"
+            % fwd.id, {}
         )
         self.assertRaises(Alias.DoesNotExist, Alias.objects.get,
                           address="forward2", domain__name="test.com")
diff --git a/modoboa/extensions/admin/tests/export.py b/modoboa/extensions/admin/tests/export.py
index 19df335a1..ca95c4b7d 100644
--- a/modoboa/extensions/admin/tests/export.py
+++ b/modoboa/extensions/admin/tests/export.py
@@ -1,6 +1,7 @@
 from django.core.urlresolvers import reverse
-from modoboa.lib.tests import ModoTestCase
+
 from modoboa.extensions.admin import factories
+from modoboa.lib.tests import ModoTestCase
 
 
 class ExportTestCase(ModoTestCase):
@@ -12,8 +13,8 @@ class ExportTestCase(ModoTestCase):
 
     def __export_identities(self, idtfilter="", grpfilter=""):
         self.clt.get(
-            reverse("admin:_identity_list") \
-                + "?grpfilter=%s&idtfilter=%s" % (grpfilter, idtfilter)
+            reverse("admin:_identity_list")
+            + "?grpfilter=%s&idtfilter=%s" % (grpfilter, idtfilter)
         )
         return self.clt.post(
             reverse("admin:identity_export"),
@@ -39,7 +40,7 @@ class ExportTestCase(ModoTestCase):
             idtfilter="account", grpfilter="SimpleUsers"
         )
         self.assertListEqual(
-            "account;user@test.com;{PLAIN}toto;;;True;SimpleUsers;user@test.com;10\r\naccount;user@test2.com;{PLAIN}toto;;;True;SimpleUsers;user@test2.com;10", 
+            "account;user@test.com;{PLAIN}toto;;;True;SimpleUsers;user@test.com;10\r\naccount;user@test2.com;{PLAIN}toto;;;True;SimpleUsers;user@test2.com;10",
             response.content.strip()
         )
 
diff --git a/modoboa/extensions/admin/tests/import_.py b/modoboa/extensions/admin/tests/import_.py
index 5195ad0e0..dee11d995 100644
--- a/modoboa/extensions/admin/tests/import_.py
+++ b/modoboa/extensions/admin/tests/import_.py
@@ -1,12 +1,13 @@
 # coding: utf-8
-from django.core.urlresolvers import reverse
 from django.core.files.base import ContentFile
+from django.core.urlresolvers import reverse
+
 from modoboa.core.models import User
-from modoboa.lib.tests import ModoTestCase
+from modoboa.extensions.admin import factories
 from modoboa.extensions.admin.models import (
     Domain, Alias, DomainAlias
 )
-from modoboa.extensions.admin import factories
+from modoboa.lib.tests import ModoTestCase
 
 
 class ImportTestCase(ModoTestCase):
@@ -76,7 +77,9 @@ dlist; dlist@test.com; True; user1@test.com; user@extdomain.com
         self.assertEqual(mb1.quota, 0)
         self.assertTrue(admin.is_owner(mb1))
         self.assertEqual(mb1.full_address, "user1@test.com")
-        self.assertTrue(self.clt.login(username="user1@test.com", password="toto"))
+        self.assertTrue(
+            self.clt.login(username="user1@test.com", password="toto")
+        )
 
         da = User.objects.get(username="truc@test.com")
         damb = da.mailbox_set.all()[0]
@@ -159,7 +162,9 @@ account; truc@test.com; toto; René; Truc; True; DomainAdmins; truc@test.com; 0;
         Expected result: no
         """
         self.clt.logout()
-        self.assertTrue(self.clt.login(username="admin@test.com", password="toto"))
+        self.assertTrue(
+            self.clt.login(username="admin@test.com", password="toto")
+        )
         f = ContentFile(b"""
 account; sa@test.com; toto; Super; Admin; True; SuperAdmins; superadmin@test.com; 50
 """, name="identities.csv")
diff --git a/modoboa/extensions/admin/views/export.py b/modoboa/extensions/admin/views/export.py
index 865371746..38fe6494f 100644
--- a/modoboa/extensions/admin/views/export.py
+++ b/modoboa/extensions/admin/views/export.py
@@ -1,17 +1,22 @@
-import csv
+"""Export related views."""
+
 import cStringIO
+import csv
+
 from rfc6266 import build_header
-from django.http import HttpResponse
-from django.shortcuts import render
-from django.core.urlresolvers import reverse
-from django.utils.translation import ugettext as _
+
 from django.contrib.auth.decorators import (
     login_required, permission_required, user_passes_test
 )
-from modoboa.extensions.admin.lib import get_domains, get_identities
+from django.core.urlresolvers import reverse
+from django.http import HttpResponse
+from django.shortcuts import render
+from django.utils.translation import ugettext as _
+
 from modoboa.extensions.admin.forms import (
     ExportIdentitiesForm, ExportDomainsForm
 )
+from modoboa.extensions.admin.lib import get_domains, get_identities
 
 
 def _export(content, filename):
@@ -46,7 +51,9 @@ def export_identities(request):
         form.is_valid()
         fp = cStringIO.StringIO()
         csvwriter = csv.writer(fp, delimiter=form.cleaned_data["sepchar"])
-        for ident in get_identities(request.user, **request.session['identities_filters']):
+        identities = get_identities(
+            request.user, **request.session['identities_filters'])
+        for ident in identities:
             ident.to_csv(csvwriter)
         content = fp.getvalue()
         fp.close()
diff --git a/modoboa/extensions/admin/views/identity.py b/modoboa/extensions/admin/views/identity.py
index bc41b2e55..58b93cebb 100644
--- a/modoboa/extensions/admin/views/identity.py
+++ b/modoboa/extensions/admin/views/identity.py
@@ -1,30 +1,29 @@
-"""
-Identity related views.
-"""
-from django.shortcuts import render
-from django.utils.translation import ugettext as _, ungettext
+"""Identity related views."""
+
 from django.contrib.auth.decorators import (
     login_required, permission_required, user_passes_test
 )
+from django.shortcuts import render
+from django.utils.translation import ugettext as _, ungettext
 from django.views.decorators.csrf import ensure_csrf_cookie
 
 import reversion
 
+from modoboa.core.models import User
+from modoboa.extensions.admin.forms import (
+    AccountForm
+)
+from modoboa.extensions.admin.lib import get_identities
+from modoboa.extensions.admin.models import Mailbox, Domain
 from modoboa.lib import parameters, events
 from modoboa.lib.exceptions import (
     PermDeniedException, BadRequest
 )
-from modoboa.lib.web_utils import (
-    _render_to_string, render_to_json_response
-)
-from modoboa.core.models import User
-from modoboa.extensions.admin.models import Mailbox, Domain
 from modoboa.lib.listing import (
     get_sort_order, get_listing_page
 )
-from modoboa.extensions.admin.lib import get_identities
-from modoboa.extensions.admin.forms import (
-    AccountForm
+from modoboa.lib.web_utils import (
+    _render_to_string, render_to_json_response
 )
 
 
@@ -80,9 +79,15 @@ def list_quotas(request):
         where = "admin_mailbox.address||'@'||admin_domain.name"
         db_type = db_type()
         if db_type == "postgres":
-            select = '(admin_quota.bytes::float / (CAST(admin_mailbox.quota AS BIGINT) * 1048576)) * 100'
+            select = (
+                "(admin_quota.bytes::float / (CAST(admin_mailbox.quota "
+                "AS BIGINT) * 1048576)) * 100"
+            )
         else:
-            select = 'admin_quota.bytes / (admin_mailbox.quota * 1048576) * 100'
+            select = (
+                "admin_quota.bytes / (admin_mailbox.quota "
+                "* 1048576) * 100"
+            )
             if db_type == "mysql":
                 where = "CONCAT(admin_mailbox.address,'@',admin_domain.name)"
         mboxes = mboxes.extra(
@@ -191,7 +196,8 @@ def remove_permission(request):
         domain = Domain.objects.get(pk=domid)
     except (User.DoesNotExist, Domain.DoesNotExist):
         raise BadRequest(_("Invalid request"))
-    if not request.user.can_access(account) or not request.user.can_access(domain):
+    if not request.user.can_access(account) or \
+       not request.user.can_access(domain):
         raise PermDeniedException
     domain.remove_admin(account)
     return render_to_json_response({})
diff --git a/modoboa/extensions/admin/views/import.py b/modoboa/extensions/admin/views/import.py
index fb1e6918f..a06a3a8cf 100644
--- a/modoboa/extensions/admin/views/import.py
+++ b/modoboa/extensions/admin/views/import.py
@@ -1,18 +1,23 @@
+"""Import related views."""
+
 import csv
-import reversion
-from django.utils.translation import ugettext as _
-from django.shortcuts import render
-from django.core.urlresolvers import reverse
+
 from django.contrib.auth.decorators import (
     login_required, permission_required, user_passes_test
 )
-from modoboa.lib import events
-from modoboa.lib.exceptions import ModoboaException, Conflict
+from django.core.urlresolvers import reverse
+from django.shortcuts import render
+from django.utils.translation import ugettext as _
+
+import reversion
+
 from modoboa.core.models import User
+from modoboa.extensions.admin.forms import ImportIdentitiesForm, ImportDataForm
 from modoboa.extensions.admin.models import (
     Domain, DomainAlias, Alias
 )
-from modoboa.extensions.admin.forms import ImportIdentitiesForm, ImportDataForm
+from modoboa.lib import events
+from modoboa.lib.exceptions import ModoboaException, Conflict
 
 
 def import_domain(user, row, formopts):
@@ -41,7 +46,8 @@ def import_domains(request):
 </ul>
 <p>The first element of each line is mandatory and must be equal to one of the previous values.</p>
 <p>You can use a different character as separator.</p>
-""" % ''.join([unicode(hlp) for hlp in events.raiseQueryEvent('ExtraDomainImportHelp')]))
+""" % ''.join([unicode(hlp) for hlp in
+               events.raiseQueryEvent('ExtraDomainImportHelp')]))
 
     ctx = dict(
         title=_("Import domains"),
diff --git a/modoboa/extensions/amavis/templatetags/amavis_tags.py b/modoboa/extensions/amavis/templatetags/amavis_tags.py
index 79b8ac9b3..f5d1a2c9a 100644
--- a/modoboa/extensions/amavis/templatetags/amavis_tags.py
+++ b/modoboa/extensions/amavis/templatetags/amavis_tags.py
@@ -80,20 +80,23 @@ def viewm_menu(user, mail_id, rcpt):
 
 @register.simple_tag
 def viewm_menu_simple(user, mail_id, rcpt, secret_id=""):
+    release_url = "{0}?rcpt={1}".format(
+        reverse("amavis:mail_release", args=[mail_id]), rcpt)
+    delete_url = "{0}?rcpt={1}".format(
+        reverse("amavis:mail_delete", args=[mail_id]), rcpt)
+    if secret_id:
+        release_url += "&secret_id={0}".format(secret_id)
+        delete_url += "&secret_id={0}".format(secret_id)
     entries = [
         {"name": "release",
          "img": "fa fa-check",
          "class": "btn-success",
-         "url": reverse('amavis:mail_release', args=[mail_id]) \
-             + ("?rcpt=%s" % rcpt \
-                    + (("&secret_id=%s" % secret_id) if secret_id != "" else "")),
+         "url": release_url,
          "label": _("Release")},
         {"name": "delete",
          "img": "fa fa-trash",
          "class": "btn-danger",
-         "url": reverse('amavis:mail_delete', args=[mail_id]) \
-             + "?rcpt=%s" % rcpt \
-             + ("&secret_id=%s" % secret_id if secret_id != "" else ""),
+         "url": delete_url,
          "label": _("Delete")},
     ]