  from django.core.urlresolvers import resolve, get_script_prefix
  from django.conf import settings
  from django.forms import widgets
  from django.utils.encoding import is_protected_type, smart_unicode
  from django.utils.translation import ugettext_lazy as _
  from rest_framework.reverse import reverse
  from rest_framework.compat import parse_date, parse_datetime
  from rest_framework.compat import timezone
  from urlparse import urlparse
 
</s> remove     Serializes a related field or related object to a pk value.
 </s> add     Represents a to-one relationship as a pk value. </s> remove     Serializes a to-many related field or related manager to a pk value.
 </s> add     Represents a to-many relationship as a pk value. </s> remove                 # If choices have friendly readable names,
                # then add in the identities too
                if getattr(widget, 'choices', None):
                    choices = widget.choices
                    if any([ident != desc for (ident, desc) in choices]):
                        choices = [(ident, "%s (%s)" % (desc, ident))
                                   for (ident, desc) in choices]
                    widget.choices = choices
 </s> add  </s> remove             if getattr(v, 'queryset', None):
                kwargs['queryset'] = v.queryset
 </s> add             #if getattr(v, 'queryset', None):
            #    kwargs['queryset'] = v.queryset

            if getattr(v, 'choices', None) is not None:
                kwargs['choices'] = v.choices
from django.forms.models import ModelChoiceIterator
  from django.core.urlresolvers import resolve, get_script_prefix
  from django.conf import settings
  from django.forms import widgets
from django.forms.models import ModelChoiceIterator
  from django.utils.encoding import is_protected_type, smart_unicode
  from django.utils.translation import ugettext_lazy as _
  from rest_framework.reverse import reverse
  from rest_framework.compat import parse_date, parse_datetime
  from rest_framework.compat import timezone
  from urlparse import urlparse
keep keep add keep keep keep keep keep keep
 Relational field support in browseable API.

Add slug relational fields.
Add quickstart. 
rest_framework/fields.py