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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 group_write(self, addr, data, dptsize=0):
 """Send a group write to the given address. The method does not check if the address exists and the write request is valid. """

        cemi = CEMIMessage()
        cemi.init_group_write(addr, data, dptsize)

        with self._lock:
            self.send_tunnelling_request(cemi)
            # Workaround for lost KNX packets
            if self._write_delay: 
                time.sleep(self._write_delay)