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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_fs(self, key: str, dms: bool = False) -> Union[str, float]: """Get float number. :param key: Key (`lt` or `lg`). :param dms: DMS format. :return: Float number """

        # Default range is a range of longitude.
        rng = (-90, 90) if key == 'lt' else (-180, 180)
        result = self.random.uniform(*rng, precision=6)

        if dms:
            return self._dd_to_dms(result, key)

        return result