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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 change_url(self, url: str, description: str = None):
 """ change the url of that attachment |methcoro| Args: url: url you want to change description: *optional* description for your attachment Raises: ValueError: url must not be None APIException """

        await self._change(url=url, description=description)