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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_strings(self):
 """ we by definition have a TZ """


        values = self.values.astype(object)
        is_dates_only = _is_dates_only(values)
        formatter = (self.formatter or
                     _get_format_datetime64(is_dates_only,
                                            date_format=self.date_format))
        fmt_values = [formatter(x) for x in values]

        return fmt_values