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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 datetime(self):
 """Conversion of the Date object into a ``datetime.datetime`` The resulting object is a timezone-naive instance with the same scale as the originating Date object. """

        if 'dt_scale' not in self._cache.keys():
            self._cache['dt_scale'] = self._datetime - timedelta(seconds=self._offset)
        return self._cache['dt_scale']