docs: def send(self, messages=None, api_key=None, secure=None, test=None,
               **request_args):
          '''Send batch request to Postmark API.
          Returns result of :func:`requests.post`.
  
          :param messages: Batch messages to send to the Postmark API.
          :type messages: A list of :class:`Message`
          :param api_key: Your Postmark API key. Defaults to `self.api_key`.
          :param test: Make a test request to the Postmark API.
              Defaults to `self.test`.
          :param secure: Use the https Postmark API. Defaults to `self.secure`.
          :param \*\*request_args: Passed to :func:`requests.request`
          :rtype: :class:`BatchSendResponse`
          '''
          return super(BatchSender, self).send(message=messages, test=test,
                                               api_key=api_key, secure=secure,
                                               **request_args)