  from __future__ import unicode_literals
  from django.db.models.fields import BLANK_CHOICE_DASH
  from django.utils.datastructures import MultiValueDict
  from django.test import TestCase
  from rest_framework import serializers
 
</s> remove     ManyToManyModel, Person, ReadOnlyManyToManyModel, Photo, SeveralChoicesModel)
 </s> add     ManyToManyModel, Person, ReadOnlyManyToManyModel, Photo) </s> remove # Model for issue #725
class SeveralChoicesModel(RESTFrameworkModel):
    color = models.CharField(
        max_length=10,
        choices=[('red', 'Red'), ('green', 'Green'), ('blue', 'Blue')],
        blank=False
    )
    drink = models.CharField(
        max_length=10,
        choices=[('beer', 'Beer'), ('wine', 'Wine'), ('cider', 'Cider')],
        blank=False,
        default='beer'
    )
    os = models.CharField(
        max_length=10,
        choices=[('linux', 'Linux'), ('osx', 'OSX'), ('windows', 'Windows')],
        blank=True
    )
    music_genre = models.CharField(
        max_length=10,
        choices=[('rock', 'Rock'), ('metal', 'Metal'), ('grunge', 'Grunge')],
        blank=True,
        default='metal'
    )


 </s> add 
from django.db import models
  from __future__ import unicode_literals
from django.db import models
  from django.db.models.fields import BLANK_CHOICE_DASH
  from django.utils.datastructures import MultiValueDict
  from django.test import TestCase
  from rest_framework import serializers
add keep keep keep keep
 Moved test model into closer to the testcase 
rest_framework/tests/serializer.py