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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 mechanism(self, mechanism):
 """ Sets the mechanism of this DeviceData. The ID of the channel used to communicate with the device. :param mechanism: The mechanism of this DeviceData. :type: str """

        allowed_values = ["connector", "direct"]
        if mechanism not in allowed_values:
            raise ValueError(
                "Invalid value for `mechanism` ({0}), must be one of {1}"
                .format(mechanism, allowed_values)
            )

        self._mechanism = mechanism