          """
          Return a two-tuple of (user, authtoken), representing an
          unauthenticated request.
  
          By default this will be (AnonymousUser, None).
          """
          if api_settings.UNAUTHENTICATED_USER:
              user = api_settings.UNAUTHENTICATED_USER()
          else:
              user = None
 
</s> remove         Return a two-tuple of (user, authtoken), representing an
        unauthenticated request.
 </s> add         Return a three-tuple of (authenticator, user, authtoken), representing
        an unauthenticated request. </s> remove                 return user_auth_tuple
 </s> add                 user, auth = user_auth_tuple
                return (authenticator, user, auth) </s> remove             self._user, self._auth = self._authenticate()
 </s> add             self._authenticator, self._user, self._auth = self._authenticate() </s> remove         return (user, auth)
 </s> add         return (None, user, auth)
        By default this will be (None, AnonymousUser, None).
          """
          Return a two-tuple of (user, authtoken), representing an
          unauthenticated request.
  
        By default this will be (None, AnonymousUser, None).
          """
          if api_settings.UNAUTHENTICATED_USER:
              user = api_settings.UNAUTHENTICATED_USER()
          else:
              user = None
keep keep keep keep replace keep keep keep keep keep
 Implementing 401 vs 403 responses 
rest_framework/request.py