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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 PLAY(self):
 """RTSP session is ready to send data."""

        message = "PLAY " + self.session.url + " RTSP/1.0\r\n"
        message += self.sequence
        message += self.authentication
        message += self.user_agent
        message += self.session_id
        message += '\r\n'
        return message