Fixed a number of flake8 errors -- particularly around unused imports and local variables

django/test/client.py

@@ -91,8 +91,6 @@ class ClientHandler(BaseHandler):
         super(ClientHandler, self).__init__(*args, **kwargs)
 
     def __call__(self, environ):
-        from django.conf import settings
-
         # Set up middleware if needed. We couldn't do this earlier, because
         # settings weren't available.
         if self._request_middleware is None: