  ########## ResponseMixin ##########
  
  class ResponseMixin(object):
      """
      Adds behavior for pluggable `Renderers` to a :class:`views.View` class.
  
      Default behavior is to use standard HTTP Accept header content negotiation.
      Also supports overriding the content type by specifying an ``_accept=`` parameter in the URL.
      Ignores Accept headers from Internet Explorer user agents and uses a sensible browser Accept header instead.
      """
 
</s> remove The :mod:`response` module provides Response classes you can use in your
views to return a certain HTTP response. Typically a response is *rendered*
into a HTTP response depending on what renderers are set on your view and
als depending on the accept header of the request.
 </s> add The :mod:`response` module provides :class:`Response` and :class:`ImmediateResponse` classes.

`Response` is a subclass of `HttpResponse`, and can be similarly instantiated and returned
from any view. It is a bit smarter than Django's `HttpResponse` though, for it knows how
to use :mod:`renderers` to automatically render its content to a serial format.
This is achieved by :

    - determining the accepted types by checking for an overload or an `Accept` header in the request
    - looking for a suitable renderer and using it on the content given at instantiation


`ImmediateResponse` is an exception that inherits from `Response`. It can be used
to abort the request handling (i.e. ``View.get``, ``View.put``, ...), 
and immediately returning a response. </s> remove # TODO: can't pass because view is a simple Django view and response is an ErrorResponse
#    def test_unsatisfiable_accept_header_on_request_returns_406_status(self):
#        """If the Accept header is unsatisfiable we should return a 406 Not Acceptable response."""
#        resp = self.client.get('/', HTTP_ACCEPT='foo/bar')
#        self.assertEquals(resp.status_code, status.HTTP_406_NOT_ACCEPTABLE)
 </s> add     @unittest.skip('can\'t pass because view is a simple Django view and response is an ImmediateResponse')
    def test_unsatisfiable_accept_header_on_request_returns_406_status(self):
        """If the Accept header is unsatisfiable we should return a 406 Not Acceptable response."""
        resp = self.client.get('/', HTTP_ACCEPT='foo/bar')
        self.assertEquals(resp.status_code, status.HTTP_406_NOT_ACCEPTABLE) </s> remove         Should be a tuple/list of classes as described in the :mod:`renderers` module.
 </s> add         `renderers` is a list/tuple of renderer instances and represents the set of renderers
        that the response can handle.
    Adds behavior for pluggable `renderers` to a :class:`views.View` class.
  ########## ResponseMixin ##########
  
  class ResponseMixin(object):
      """
    Adds behavior for pluggable `renderers` to a :class:`views.View` class.
  
      Default behavior is to use standard HTTP Accept header content negotiation.
      Also supports overriding the content type by specifying an ``_accept=`` parameter in the URL.
      Ignores Accept headers from Internet Explorer user agents and uses a sensible browser Accept header instead.
      """
keep keep keep keep replace keep keep keep keep keep
 cleaned a bit Response/ResponseMixin code, added some documentation + renamed ErrorResponse to ImmediateResponse 
djangorestframework/mixins.py