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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 modify_data(self, message):
 """Update the contents of this periodically sent message. Note the Message must have the same :attr:`~can.Message.arbitration_id` like the first message. """

        assert message.arbitration_id == self.can_id, "You cannot modify the can identifier"
        self.message = message
        header = build_bcm_update_header(self.can_id_with_flags, self.flags)
        frame = build_can_frame(message)
        send_bcm(self.bcm_socket, header + frame)