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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 remove_sensor(self, sensor):
 """Remove a sensor from the device. Also deregisters all clients observing the sensor. Parameters sensor : Sensor object or name string The sensor to remove from the device server. """

        if isinstance(sensor, basestring):
            sensor_name = sensor
        else:
            sensor_name = sensor.name
        sensor = self._sensors.pop(sensor_name)

        def cancel_sensor_strategies():
            for conn_strategies in self._strategies.values():
                strategy = conn_strategies.pop(sensor, None)
                if strategy:
                    strategy.cancel()
        self.ioloop.add_callback(cancel_sensor_strategies)