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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 _gps_scale_factory(unit):
 """Construct a GPSScale for this unit """

    class FixedGPSScale(GPSScale):
        """`GPSScale` for a specific GPS time unit
        """
        name = str('{0}s'.format(unit.long_names[0] if unit.long_names else
                                 unit.names[0]))

        def __init__(self, axis, epoch=None):
            """
            """
            super(FixedGPSScale, self).__init__(axis, epoch=epoch, unit=unit)
    return FixedGPSScale