diff --git a/graphql/backend/base.py b/graphql/backend/base.py
index 6573d3a7..03026dc1 100644
--- a/graphql/backend/base.py
+++ b/graphql/backend/base.py
@@ -1,9 +1,8 @@
-from ..pyutils.cached_property import cached_property
-from ..language import ast
-
 from abc import ABCMeta, abstractmethod
 import six
 
+from ..pyutils.cached_property import cached_property
+from ..language import ast
 
 # Necessary for static type checking
 if False:  # flake8: noqa
diff --git a/graphql/backend/cache.py b/graphql/backend/cache.py
index f35a45ca..ef277966 100644
--- a/graphql/backend/cache.py
+++ b/graphql/backend/cache.py
@@ -1,8 +1,8 @@
 from hashlib import sha1
 
 from six import string_types
-from ..type import GraphQLSchema
 
+from ..type import GraphQLSchema
 from .base import GraphQLBackend
 
 # Necessary for static type checking
diff --git a/graphql/backend/compiled.py b/graphql/backend/compiled.py
index 91183f77..d58e4e24 100644
--- a/graphql/backend/compiled.py
+++ b/graphql/backend/compiled.py
@@ -1,4 +1,5 @@
 from six import string_types
+
 from .base import GraphQLDocument
 
 # Necessary for static type checking
diff --git a/graphql/backend/core.py b/graphql/backend/core.py
index 41aea2d6..e8fc3099 100644
--- a/graphql/backend/core.py
+++ b/graphql/backend/core.py
@@ -1,11 +1,11 @@
 from functools import partial
+
 from six import string_types
 
 from ..execution import execute, ExecutionResult
 from ..language.base import parse, print_ast
 from ..language import ast
 from ..validation import validate
-
 from .base import GraphQLBackend, GraphQLDocument
 
 # Necessary for static type checking
diff --git a/graphql/backend/decider.py b/graphql/backend/decider.py
index 5fdd39bb..ca6f69d0 100644
--- a/graphql/backend/decider.py
+++ b/graphql/backend/decider.py
@@ -4,10 +4,9 @@
 import os
 from time import sleep, time
 
-
+from ..pyutils.compat import Queue, check_threads
 from .base import GraphQLBackend, GraphQLDocument
 from .cache import GraphQLCachedBackend
-from ..pyutils.compat import Queue, check_threads
 
 # Necessary for static type checking
 if False:  # flake8: noqa
diff --git a/graphql/backend/quiver_cloud.py b/graphql/backend/quiver_cloud.py
index 2c6796b6..7d753820 100644
--- a/graphql/backend/quiver_cloud.py
+++ b/graphql/backend/quiver_cloud.py
@@ -6,13 +6,12 @@
         "You can install it using: pip install requests"
     )
 
-from ..utils.schema_printer import print_schema
+from six.moves.urllib.parse import urlparse
 
+from ..utils.schema_printer import print_schema
 from .base import GraphQLBackend
 from .compiled import GraphQLCompiledDocument
 
-from six.moves.urllib.parse import urlparse
-
 GRAPHQL_QUERY = """
 mutation($schemaDsl: String!, $query: String!, $pythonOptions: PythonOptions) {
   generateCode(
diff --git a/graphql/error/base.py b/graphql/error/base.py
index 0aae96b0..2865e4a4 100644
--- a/graphql/error/base.py
+++ b/graphql/error/base.py
@@ -1,4 +1,5 @@
 import six
+
 from ..language.location import get_location
 
 # Necessary for static type checking
diff --git a/tests_py35/core_execution/test_asyncio_executor.py b/tests_py35/core_execution/test_asyncio_executor.py
index 8d5334d5..2bfff7c5 100644
--- a/tests_py35/core_execution/test_asyncio_executor.py
+++ b/tests_py35/core_execution/test_asyncio_executor.py
@@ -1,7 +1,5 @@
-# flake8: noqa
-import pytest
 import asyncio
-import functools
+
 from graphql.error import format_error
 from graphql.execution import execute
 from graphql.language.parser import parse