  from django.core.urlresolvers import resolve, get_script_prefix, NoReverseMatch
  from django import forms
  from django.forms import widgets
  from django.forms.models import ModelChoiceIterator
  from django.utils.translation import ugettext_lazy as _
  from rest_framework.fields import Field, WritableField, get_component
  from rest_framework.reverse import reverse
 
</s> remove         self.queryset = kwargs.pop('queryset', None)
 </s> add         queryset = kwargs.pop('queryset', None)
from django.db.models.fields import BLANK_CHOICE_DASH
  from django.core.urlresolvers import resolve, get_script_prefix, NoReverseMatch
  from django import forms
from django.db.models.fields import BLANK_CHOICE_DASH
  from django.forms import widgets
  from django.forms.models import ModelChoiceIterator
  from django.utils.translation import ugettext_lazy as _
  from rest_framework.fields import Field, WritableField, get_component
  from rest_framework.reverse import reverse
keep add keep keep keep keep keep
 Display an empty label into related fields if it isn't required 
rest_framework/relations.py