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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 local_machine_uuid():
 """Return local machine unique identifier. """


    result = subprocess.check_output(
        'hal-get-property --udi '
        '/org/freedesktop/Hal/devices/computer '
        '--key system.hardware.uuid'.split()
        ).strip()

    return uuid.UUID(hex=result)