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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 is_distinct(self):
 """True if results are guaranteed to contain a unique set of property values. This happens when every property in the group_by is also in the projection. """

    return bool(self.__group_by and
                set(self._to_property_names(self.__group_by)) <=
                set(self._to_property_names(self.__projection)))