diff --git a/mayan/apps/common/templatetags/common_tags.py b/mayan/apps/common/templatetags/common_tags.py
index b6ed9f6583..0332231227 100644
--- a/mayan/apps/common/templatetags/common_tags.py
+++ b/mayan/apps/common/templatetags/common_tags.py
@@ -18,7 +18,6 @@ try:
     BUILD = sh.Command('git').bake('describe', '--tags', '--always', 'HEAD')
     DATE = sh.Command('git').bake('--no-pager', 'log', '-1', '--format=%cd')
 except sh.CommandNotFound:
-    logger.debug('git not found')
     BUILD = None
     DATE = None
 
diff --git a/mayan/apps/converter/exceptions.py b/mayan/apps/converter/exceptions.py
index 62087a602b..a00cae5a2d 100644
--- a/mayan/apps/converter/exceptions.py
+++ b/mayan/apps/converter/exceptions.py
@@ -30,5 +30,6 @@ class OfficeConversionError(ConvertError):
 class InvalidOfficeFormat(ConvertError):
     pass
 
+
 class PageCountError(ConvertError):
     pass
diff --git a/mayan/apps/documents/models.py b/mayan/apps/documents/models.py
index 7c016b9863..8167a2d4a8 100644
--- a/mayan/apps/documents/models.py
+++ b/mayan/apps/documents/models.py
@@ -21,7 +21,7 @@ from converter import (
     TransformationZoom
 )
 from converter.exceptions import (
-    InvalidOfficeFormat, PageCountError, UnknownFileFormat
+    InvalidOfficeFormat, PageCountError
 )
 from converter.literals import DEFAULT_ZOOM_LEVEL, DEFAULT_ROTATION
 from converter.models import Transformation
diff --git a/mayan/apps/documents/test_api.py b/mayan/apps/documents/test_api.py
index 492ce77e48..059af0170e 100644
--- a/mayan/apps/documents/test_api.py
+++ b/mayan/apps/documents/test_api.py
@@ -15,7 +15,7 @@ from .models import Document, DocumentType
 from .test_models import (
     TEST_ADMIN_EMAIL, TEST_ADMIN_PASSWORD, TEST_ADMIN_USERNAME,
     TEST_DOCUMENT_FILENAME, TEST_DOCUMENT_PATH, TEST_DOCUMENT_TYPE,
-    TEST_SMALL_DOCUMENT_FILENAME, TEST_SMALL_DOCUMENT_PATH,
+    TEST_SMALL_DOCUMENT_PATH,
 )
 
 
diff --git a/mayan/apps/folders/api_views.py b/mayan/apps/folders/api_views.py
index 07904b0fae..7628cfe0f7 100644
--- a/mayan/apps/folders/api_views.py
+++ b/mayan/apps/folders/api_views.py
@@ -3,13 +3,12 @@ from __future__ import absolute_import, unicode_literals
 from django.core.exceptions import PermissionDenied
 from django.shortcuts import get_object_or_404
 
-from rest_framework import generics, status, views
+from rest_framework import generics
 from rest_framework.response import Response
 
 from acls.models import AccessControlList
-from documents.models import Document, DocumentType
+from documents.models import Document
 from documents.permissions import permission_document_view
-from documents.serializers import DocumentSerializer
 from permissions import Permission
 from rest_api.filters import MayanObjectPermissionsFilter
 from rest_api.permissions import MayanPermission
@@ -221,8 +220,8 @@ class APIFolderDocumentView(generics.RetrieveDestroyAPIView):
                 self.request.user, (permission_document_view,)
             )
         except PermissionDenied:
-            documents = AccessControlList.objects.check_access(
-                permission_document_view, self.request.user, documents
+            AccessControlList.objects.check_access(
+                permission_document_view, self.request.user, instance
             )
 
         serializer = self.get_serializer(instance)
diff --git a/mayan/apps/folders/test_api.py b/mayan/apps/folders/test_api.py
index 254a46e135..7a0305cb44 100644
--- a/mayan/apps/folders/test_api.py
+++ b/mayan/apps/folders/test_api.py
@@ -1,19 +1,15 @@
 from __future__ import unicode_literals
 
-from json import loads
-
 from django.contrib.auth.models import User
 from django.core.files import File
 from django.core.urlresolvers import reverse
 
-from rest_framework import status
 from rest_framework.test import APITestCase
 
 from documents.models import DocumentType
 from documents.test_models import (
     TEST_ADMIN_EMAIL, TEST_ADMIN_PASSWORD, TEST_ADMIN_USERNAME,
-    TEST_DOCUMENT_FILENAME, TEST_DOCUMENT_PATH, TEST_DOCUMENT_TYPE,
-    TEST_SMALL_DOCUMENT_FILENAME, TEST_SMALL_DOCUMENT_PATH,
+    TEST_DOCUMENT_TYPE, TEST_SMALL_DOCUMENT_PATH,
 )
 
 from .models import Folder
diff --git a/mayan/apps/mailer/models.py b/mayan/apps/mailer/models.py
index 668bb7d096..ac05b4b71f 100644
--- a/mayan/apps/mailer/models.py
+++ b/mayan/apps/mailer/models.py
@@ -3,12 +3,8 @@ from __future__ import unicode_literals
 import logging
 
 from django.db import models
-from django.utils.encoding import python_2_unicode_compatible
 from django.utils.translation import ugettext_lazy as _
 
-from djcelery.models import PeriodicTask, IntervalSchedule
-from documents.models import Document
-
 logger = logging.getLogger(__name__)
 
 
diff --git a/mayan/apps/ocr/exceptions.py b/mayan/apps/ocr/exceptions.py
index d7ea77f674..9fc7a9b90a 100644
--- a/mayan/apps/ocr/exceptions.py
+++ b/mayan/apps/ocr/exceptions.py
@@ -20,4 +20,3 @@ class NoMIMETypeMatch(ParserError):
     There is no parser registered for the specified MIME type
     """
     pass
-
diff --git a/mayan/apps/ocr/parsers.py b/mayan/apps/ocr/parsers.py
index efc65b5517..c8285499ef 100644
--- a/mayan/apps/ocr/parsers.py
+++ b/mayan/apps/ocr/parsers.py
@@ -40,10 +40,10 @@ class Parser(object):
     @classmethod
     def process_document_version(cls, document_version):
         try:
-            for parser_class in cls._registry[mimetype]:
+            for parser_class in cls._registry[document_version.mimetype]:
                 try:
                     parser = parser_class()
-                    parser.process_document_version(document_page)
+                    parser.process_document_version(document_version)
                 except ParserError:
                     # If parser raises error, try next parser in the list
                     pass
@@ -158,7 +158,7 @@ class PDFMinerParser(Parser):
             rsrcmgr = PDFResourceManager()
             device = TextConverter(rsrcmgr, outfp=string_buffer, laparams=LAParams())
             interpreter = PDFPageInterpreter(rsrcmgr, device)
-            page = PDFPage.get_pages(file_object, maxpages=1, pagenos=(page_number-1,))
+            page = PDFPage.get_pages(file_object, maxpages=1, pagenos=(page_number - 1,))
             interpreter.process_page(page.next())
             device.close()
 
diff --git a/mayan/apps/ocr/test_parsers.py b/mayan/apps/ocr/test_parsers.py
index c46c21edcb..3dbd97164b 100644
--- a/mayan/apps/ocr/test_parsers.py
+++ b/mayan/apps/ocr/test_parsers.py
@@ -5,10 +5,7 @@ from django.core.files.base import File
 from django.test import TestCase
 
 from documents.models import DocumentType
-from documents.settings import setting_language_choices
-from documents.test_models import (
-    TEST_DOCUMENT_PATH, TEST_DOCUMENT_TYPE, TEST_SMALL_DOCUMENT_PATH
-)
+from documents.test_models import TEST_DOCUMENT_PATH, TEST_DOCUMENT_TYPE
 
 from .parsers import PDFMinerParser, PopplerParser
 
diff --git a/mayan/apps/tags/api_views.py b/mayan/apps/tags/api_views.py
index 552777efd0..79726395de 100644
--- a/mayan/apps/tags/api_views.py
+++ b/mayan/apps/tags/api_views.py
@@ -3,7 +3,7 @@ from __future__ import absolute_import, unicode_literals
 from django.core.exceptions import PermissionDenied
 from django.shortcuts import get_object_or_404
 
-from rest_framework import generics, status, views
+from rest_framework import generics
 from rest_framework.exceptions import ValidationError
 from rest_framework.response import Response
 
@@ -17,8 +17,8 @@ from rest_api.permissions import MayanPermission
 
 from .models import Tag
 from .permissions import (
-    permission_tag_attach, permission_tag_create, permission_tag_delete,
-    permission_tag_edit, permission_tag_remove, permission_tag_view
+    permission_tag_create, permission_tag_delete, permission_tag_edit,
+    permission_tag_remove, permission_tag_view
 )
 from .serializers import (
     DocumentTagSerializer, NewDocumentTagSerializer, TagSerializer
@@ -110,7 +110,7 @@ class APITagDocumentListView(generics.ListAPIView):
 
         return tag.documents.all()
 
-###
+
 class APIDocumentTagListView(generics.ListCreateAPIView):
     """
     Returns a list of all the tags attached to a document.
@@ -193,7 +193,7 @@ class APIDocumentTagView(generics.RetrieveDestroyAPIView):
                 self.request.user, (permission_document_view,)
             )
         except PermissionDenied:
-            documents = AccessControlList.objects.check_access(
+            AccessControlList.objects.check_access(
                 permission_document_view, self.request.user, document
             )
         return document
diff --git a/mayan/apps/tags/serializers.py b/mayan/apps/tags/serializers.py
index fbbc8f0f3d..439a500225 100644
--- a/mayan/apps/tags/serializers.py
+++ b/mayan/apps/tags/serializers.py
@@ -40,7 +40,7 @@ class NewDocumentTagSerializer(serializers.Serializer):
                 Permission.check_permissions(self.context['request'].user, (permission_tag_attach,))
             except PermissionDenied:
                 AccessControlList.objects.check_access(
-                    permission_tag_attach, self.context['request'], document
+                    permission_tag_attach, self.context['request'], tag
                 )
 
             tag.documents.add(validated_data['document'])
diff --git a/mayan/apps/user_management/serializers.py b/mayan/apps/user_management/serializers.py
index ec06407bdf..bd21f1ada9 100644
--- a/mayan/apps/user_management/serializers.py
+++ b/mayan/apps/user_management/serializers.py
@@ -41,4 +41,3 @@ class UserSerializer(serializers.HyperlinkedModelSerializer):
         if 'password' in attrs:
             user.set_password(attrs['password'])
         return user
-