  from collections import OrderedDict
  
  from django.utils.encoding import force_text
  
  from rest_framework.compat import unicode_to_repr
  from rest_framework.utils import json
  
  
  class ReturnDict(OrderedDict):
      """
 
</s> remove import collections
 </s> add  </s> remove     MaxLengthValidator, MaxValueValidator, MinLengthValidator,
 </s> add     Mapping, MaxLengthValidator, MaxValueValidator, MinLengthValidator, </s> remove     from collections import Mapping   # noqa
 </s> add     from collections import Mapping, MutableMapping   # noqa </s> remove     from collections.abc import Mapping   # noqa
 </s> add     from collections.abc import Mapping, MutableMapping   # noqa </s> remove import collections
 </s> add 
from rest_framework.compat import MutableMapping, unicode_to_repr
  from collections import OrderedDict
  
  from django.utils.encoding import force_text
  
from rest_framework.compat import MutableMapping, unicode_to_repr
  from rest_framework.utils import json
  
  
  class ReturnDict(OrderedDict):
      """
keep keep keep keep replace keep keep keep keep keep
 Fix DeprecationWarning when accessing collections.abc classes via collections (#6268)

* Use compat version of collections.abc.Mapping

Since the Mapping class will no longer be available to import directly
from the collections module in Python 3.8, we should use the
compatibility helper introduced in #6154 in the fields module.

* Alias and use compat version of collections.abc.MutableMapping

Since the MutableMapping class will no longer be available to import
directly from the collections module in Python 3.8, we should create an
alias for it in the compat module and use that instead. 
rest_framework/utils/serializer_helpers.py