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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 unpack(self, message):
 """Called to extract a STOMP message into this instance. message: This is a text string representing a valid STOMP (v1.0) message. information, before it is assigned internally. retuned: """

        if not message:
            raise FrameError("Unpack error! The given message isn't valid '%s'!" % message)

        msg = unpack_frame(message)

        self.cmd = msg['cmd']
        self.headers = msg['headers']

        # Assign directly as the message will have the null
        # character in the message already.
        self.body = msg['body']

        return msg