  from django.core.urlresolvers import resolve, get_script_prefix, NoReverseMatch, Resolver404
  from django.db.models.query import QuerySet
  from django.utils.translation import ugettext_lazy as _
  
  
  class RelatedField(Field):
 
</s> remove from django.db.models.query import QuerySet
 </s> add  </s> remove from django.utils import timezone
 </s> add from django.utils import six, timezone
from django.utils import six
  from django.core.urlresolvers import resolve, get_script_prefix, NoReverseMatch, Resolver404
  from django.db.models.query import QuerySet
from django.utils import six
  from django.utils.translation import ugettext_lazy as _
  
  
  class RelatedField(Field):
keep add keep keep keep keep
 Use six.text_type instead of str everywhere 
rest_framework/relations.py