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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:
 async def unpin_chat_message(self, chat_id: typing.Union[base.Integer, base.String]) -> base.Boolean: """ Use this method to unpin a message in a supergroup chat. The bot must be an administrator in the chat for this to work and must have the appropriate admin rights. Source: https://core.telegram.org/bots/api#unpinchatmessage :param chat_id: Unique identifier for the target chat or username of the target supergroup :type chat_id: :obj:`typing.Union[base.Integer, base.String]` :return: Returns True on success :rtype: :obj:`base.Boolean` """

        payload = generate_payload(**locals())

        result = await self.request(api.Methods.UNPIN_CHAT_MESSAGE, payload)
        return result