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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 _format_native_types(self, na_rep='', quoting=None, **kwargs):
 """ Actually format specific types of the index. """

        mask = isna(self)
        if not self.is_object() and not quoting:
            values = np.asarray(self).astype(str)
        else:
            values = np.array(self, dtype=object, copy=True)

        values[mask] = na_rep
        return values