              raise ValidationError('Could not resolve URL for field using view name "%s"' % view_name)
  
          kwargs = {self.slug_url_kwarg: slug}
          try:
              return reverse(self.view_name, kwargs=kwargs, request=request)
          except:
              pass
  
          kwargs = {self.pk_url_kwarg: obj.pk, self.slug_url_kwarg: slug}
          try:
 
</s> remove             return reverse(self.view_name, kwargs=kwargs, request=request)
 </s> add             return reverse(self.view_name, kwargs=kwargs, request=request, format=format) </s> remove             return reverse(view_name, kwargs=kwargs, request=request)
 </s> add             return reverse(view_name, kwargs=kwargs, request=request, format=format) </s> remove             raise exceptions.InvalidFormat(format)
 </s> add             raise Http404
            return reverse(self.view_name, kwargs=kwargs, request=request, format=format)
              raise ValidationError('Could not resolve URL for field using view name "%s"' % view_name)
  
          kwargs = {self.slug_url_kwarg: slug}
          try:
            return reverse(self.view_name, kwargs=kwargs, request=request, format=format)
          except:
              pass
  
          kwargs = {self.pk_url_kwarg: obj.pk, self.slug_url_kwarg: slug}
          try:
keep keep keep keep replace keep keep keep keep keep
 Fixes for urls with suffixes 
rest_framework/fields.py