diff --git a/mongoengine/queryset/__init__.py b/mongoengine/queryset/__init__.py
index 026a7acd..c8fa09db 100644
--- a/mongoengine/queryset/__init__.py
+++ b/mongoengine/queryset/__init__.py
@@ -1,6 +1,6 @@
-from mongoengine.errors import (DoesNotExist, MultipleObjectsReturned,
-                                InvalidQueryError, OperationError,
-                                NotUniqueError)
+from mongoengine.errors import (DoesNotExist, InvalidQueryError,
+                                MultipleObjectsReturned, NotUniqueError,
+                                OperationError)
 from mongoengine.queryset.field_list import *
 from mongoengine.queryset.manager import *
 from mongoengine.queryset.queryset import *
diff --git a/mongoengine/queryset/base.py b/mongoengine/queryset/base.py
index 38af72ff..8b99d69c 100644
--- a/mongoengine/queryset/base.py
+++ b/mongoengine/queryset/base.py
@@ -7,20 +7,19 @@ import pprint
 import re
 import warnings
 
-from bson import SON
+from bson import SON, json_util
 from bson.code import Code
-from bson import json_util
 import pymongo
 import pymongo.errors
 from pymongo.common import validate_read_preference
 
 from mongoengine import signals
+from mongoengine.base.common import get_document
+from mongoengine.common import _import_class
 from mongoengine.connection import get_db
 from mongoengine.context_managers import switch_db
-from mongoengine.common import _import_class
-from mongoengine.base.common import get_document
-from mongoengine.errors import (OperationError, NotUniqueError,
-                                InvalidQueryError, LookUpError)
+from mongoengine.errors import (InvalidQueryError, LookUpError,
+                                NotUniqueError, OperationError)
 from mongoengine.python_support import IS_PYMONGO_3
 from mongoengine.queryset import transform
 from mongoengine.queryset.field_list import QueryFieldList
@@ -155,10 +154,8 @@ class BaseQuerySet(object):
         # forse load cursor
         # self._cursor
 
-
     def __getitem__(self, key):
-        """Support skip and limit using getitem and slicing syntax.
-        """
+        """Support skip and limit using getitem and slicing syntax."""
         queryset = self.clone()
 
         # Slice provided
@@ -529,8 +526,9 @@ class BaseQuerySet(object):
         .. versionadded:: 0.10.2
         """
 
-        atomic_update = self.update(multi=False, upsert=True, write_concern=write_concern,
-                             full_result=True, **update)
+        atomic_update = self.update(multi=False, upsert=True,
+                                    write_concern=write_concern,
+                                    full_result=True, **update)
 
         if atomic_update['updatedExisting']:
             document = self.get()
diff --git a/mongoengine/queryset/queryset.py b/mongoengine/queryset/queryset.py
index 5121463b..e68537d2 100644
--- a/mongoengine/queryset/queryset.py
+++ b/mongoengine/queryset/queryset.py
@@ -1,6 +1,6 @@
 from mongoengine.errors import OperationError
-from mongoengine.queryset.base import (BaseQuerySet, DO_NOTHING, NULLIFY,
-                                       CASCADE, DENY, PULL)
+from mongoengine.queryset.base import (BaseQuerySet, CASCADE, DENY, DO_NOTHING,
+                                       NULLIFY, PULL)
 
 __all__ = ('QuerySet', 'QuerySetNoCache', 'DO_NOTHING', 'NULLIFY', 'CASCADE',
            'DENY', 'PULL')
diff --git a/mongoengine/queryset/transform.py b/mongoengine/queryset/transform.py
index e5e7f83f..54371d6b 100644
--- a/mongoengine/queryset/transform.py
+++ b/mongoengine/queryset/transform.py
@@ -1,11 +1,11 @@
 from collections import defaultdict
 
-import pymongo
 from bson import SON
+import pymongo
 
 from mongoengine.base.fields import UPDATE_OPERATORS
-from mongoengine.connection import get_connection
 from mongoengine.common import _import_class
+from mongoengine.connection import get_connection
 from mongoengine.errors import InvalidQueryError
 from mongoengine.python_support import IS_PYMONGO_3
 
@@ -108,8 +108,11 @@ def query(_doc_cls=None, **kwargs):
             elif op in ('match', 'elemMatch'):
                 ListField = _import_class('ListField')
                 EmbeddedDocumentField = _import_class('EmbeddedDocumentField')
-                if (isinstance(value, dict) and isinstance(field, ListField) and
-                    isinstance(field.field, EmbeddedDocumentField)):
+                if (
+                    isinstance(value, dict) and
+                    isinstance(field, ListField) and
+                    isinstance(field.field, EmbeddedDocumentField)
+                ):
                     value = query(field.field.document_type, **value)
                 else:
                     value = field.prepare_query_value(op, value)