def tz_convert(self, tz):
tz = timezones.maybe_get_tz(tz)<EOL>if self.tz is None:<EOL><INDENT>raise TypeError('<STR_LIT>'<EOL>'<STR_LIT>')<EOL><DEDENT>dtype = tz_to_dtype(tz)<EOL>return self._simple_new(self.asi8, dtype=dtype, freq=self.freq)<EOL>
Convert tz-aware Datetime Array/Index from one time zone to another.

Parameters
----------
tz : str, pytz.timezone, dateutil.tz.tzfile or None
    Time zone for time. Corresponding timestamps would be converted
    to this time zone of the Datetime Array/Index. A `tz` of None will
    convert to UTC and remove the timezone information.

Returns
-------
Array or Index

Raises
------
TypeError
    If Datetime Array/Index is tz-naive.

See Also
--------
DatetimeIndex.tz : A timezone that has a variable offset from UTC.
DatetimeIndex.tz_localize : Localize tz-naive DatetimeIndex to a
    given time zone, or remove timezone from a tz-aware DatetimeIndex.

Examples
--------
With the `tz` parameter, we can change the DatetimeIndex
to other time zones:

>>> dti = pd.date_range(start='2014-08-01 09:00',
...                     freq='H', periods=3, tz='Europe/Berlin')

>>> dti
DatetimeIndex(['2014-08-01 09:00:00+02:00',
               '2014-08-01 10:00:00+02:00',
               '2014-08-01 11:00:00+02:00'],
              dtype='datetime64[ns, Europe/Berlin]', freq='H')

>>> dti.tz_convert('US/Central')
DatetimeIndex(['2014-08-01 02:00:00-05:00',
               '2014-08-01 03:00:00-05:00',
               '2014-08-01 04:00:00-05:00'],
              dtype='datetime64[ns, US/Central]', freq='H')

With the ``tz=None``, we can remove the timezone (after converting
to UTC if necessary):

>>> dti = pd.date_range(start='2014-08-01 09:00', freq='H',
...                     periods=3, tz='Europe/Berlin')

>>> dti
DatetimeIndex(['2014-08-01 09:00:00+02:00',
               '2014-08-01 10:00:00+02:00',
               '2014-08-01 11:00:00+02:00'],
                dtype='datetime64[ns, Europe/Berlin]', freq='H')

>>> dti.tz_convert(None)
DatetimeIndex(['2014-08-01 07:00:00',
               '2014-08-01 08:00:00',
               '2014-08-01 09:00:00'],
                dtype='datetime64[ns]', freq='H')