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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 axis_updated(self, event: InputEvent, prefix=None):
 """ Called to process an absolute axis event from evdev, this is called internally by the controller implementations :internal: :param event: The evdev event to process :param prefix: If present, a named prefix that should be applied to the event code when searching for the axis """

        if prefix is not None:
            axis = self.axes_by_code.get(prefix + str(event.code))
        else:
            axis = self.axes_by_code.get(event.code)
        if axis is not None:
            axis.receive_device_value(event.value)
        else:
            logger.debug('Unknown axis code {} ({}), value {}'.format(event.code, prefix, event.value))