Forwards an attachment

        :param attachment_id: Attachment ID to forward
        :param thread_id: User/Group ID to send to. See :ref:`intro_threads`
        :raises: FBchatException if request failed

def forwardAttachment(self, attachment_id, thread_id=None):
        """
        Forwards an attachment

        :param attachment_id: Attachment ID to forward
        :param thread_id: User/Group ID to send to. See :ref:`intro_threads`
        :raises: FBchatException if request failed
        """
        thread_id, thread_type = self._getThread(thread_id, None)
        data = {
            "attachment_id": attachment_id,
            "recipient_map[{}]".format(generateOfflineThreadingID()): thread_id,
        }
        j = self._post(
            self.req_url.FORWARD_ATTACHMENT, data, fix_request=True, as_json=True
        )