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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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
        )