code: def _maybe_coerce_values(self, values):
          
          if not isinstance(values, self._holder):
              values = self._holder(values)
  
          if values.tz is None:
              raise ValueError("cannot create a DatetimeTZBlock without a tz")
  
          return values
docs: 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