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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 get_unit_name(self):
 """Returns the name of the unit for this GPS scale Note that this returns a simply-pluralised version of the name. """

        if not self.unit:
            return None
        name = sorted(self.unit.names, key=len)[-1]
        return '%ss' % name