          Returns any non-user authentication information associated with the
          request, such as an authentication token.
          """
          if not hasattr(self, '_auth'):
              self._user, self._auth = self._authenticate()
          return self._auth
  
      def _load_data_and_files(self):
          """
          Parses the request content into self.DATA and self.FILES.
 
</s> remove             self._user, self._auth = self._authenticate()
 </s> add             self._authenticator, self._user, self._auth = self._authenticate() </s> remove         Attempt to authenticate the request using each authentication instance in turn.
        Returns a two-tuple of (user, authtoken).
 </s> add         Attempt to authenticate the request using each authentication instance
        in turn.
        Returns a three-tuple of (authenticator, user, authtoken).
            self._authenticator, self._user, self._auth = self._authenticate()
          Returns any non-user authentication information associated with the
          request, such as an authentication token.
          """
          if not hasattr(self, '_auth'):
            self._authenticator, self._user, self._auth = self._authenticate()
          return self._auth
  
      def _load_data_and_files(self):
          """
          Parses the request content into self.DATA and self.FILES.
keep keep keep keep replace keep keep keep keep keep
 Implementing 401 vs 403 responses 
rest_framework/request.py