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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 set(self, val):
 """Set the heat set point."""

        msg = ExtendedSend(
            address=self._address,
            commandtuple=COMMAND_THERMOSTAT_SET_HEAT_SETPOINT_0X6D_NONE,
            cmd2=int(val * 2),
            userdata=Userdata())
        msg.set_checksum()
        self._send_method(msg, self._set_heat_point_ack)