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Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def tweet(self, text, in_reply_to=None, filename=None, file=None):
 """ Post a new tweet. :param text: the text to post :param in_reply_to: The ID of the tweet to reply to :param filename: If `file` param is not provided, read file from this path :param file: A file object, which will be used instead of opening `filename`. `filename` is still required, for MIME type detection and to use as a form field in the POST data :return: Tweet object """


        if filename is None:
            return Tweet(self._client.update_status(status=text, in_reply_to_status_id=in_reply_to)._json)
        else:
            return Tweet(self._client.update_with_media(filename=filename, file=file,
                                                        status=text, in_reply_to_status_id=in_reply_to)._json)