  from __future__ import unicode_literals
  from django.core.cache import cache as default_cache
  from django.core.exceptions import ImproperlyConfigured
  from rest_framework.settings import api_settings
  import time
  
  
  class BaseThrottle(object):
      """
      Rate throttling of requests.
 
</s> remove from django.core.exceptions import PermissionDenied
from django.http import Http404
 </s> add import inspect
import warnings
 </s> remove from django.core.exceptions import ImproperlyConfigured
from django.db import models
 </s> add import operator
from functools import reduce
 </s> remove from rest_framework.compat import django_filters, guardian, get_model_name
 </s> add from django.db import models
from django.core.exceptions import ImproperlyConfigured

  from __future__ import unicode_literals
  from django.core.cache import cache as default_cache
  from django.core.exceptions import ImproperlyConfigured
  from rest_framework.settings import api_settings

  
  
  class BaseThrottle(object):
      """
      Rate throttling of requests.
keep keep keep keep replace keep keep keep keep keep
 Cleanup import following PEP 8 style guide 
rest_framework/throttling.py