  # cStringIO only if it's available, otherwise StringIO
  try:
      import cStringIO as StringIO
  except ImportError:
      import StringIO
  
  
  def get_concrete_model(model_cls):
      try:
          return model_cls._meta.concrete_model
 
</s> remove from django.utils.encoding import smart_unicode
 </s> add try:
    from django.utils.encoding import smart_text
except ImportError:
    from django.utils.encoding import smart_unicode as smart_text </s> remove from StringIO import StringIO
 </s> add from rest_framework.compat import StringIO </s> remove from StringIO import StringIO
 </s> add from rest_framework.compat import StringIO </s> remove import StringIO
 </s> add from rest_framework.compat import StringIO
 </s> remove from StringIO import StringIO
 </s> add from rest_framework.compat import StringIO
    from six import StringIO
  # cStringIO only if it's available, otherwise StringIO
  try:
      import cStringIO as StringIO
  except ImportError:
    from six import StringIO
  
  
  def get_concrete_model(model_cls):
      try:
          return model_cls._meta.concrete_model
keep keep keep keep replace keep keep keep keep keep
 First passing test under p3k \o/ 
rest_framework/compat.py