def _maybe_coerce_values(self, values):
if not isinstance(values, self._holder):<EOL><INDENT>values = self._holder(values)<EOL><DEDENT>if values.tz is None:<EOL><INDENT>raise ValueError("<STR_LIT>")<EOL><DEDENT>return values<EOL>
Input validation for values passed to __init__. Ensure that
        we have datetime64TZ, coercing if necessary.

        Parametetrs
        -----------
        values : array-like
            Must be convertible to datetime64

        Returns
        -------
        values : DatetimeArray