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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 timezone(self, location, at_time=None, timeout=DEFAULT_SENTINEL):
 """ Find the timezone a `location` was in for a specified `at_time`, and return a pytz timezone object. .. versionadded:: 1.2.0 .. deprecated:: 1.18.0 Use :meth:`GoogleV3.reverse_timezone` instead. This method will be removed in geopy 2.0. .. versionchanged:: 1.18.1 Previously a :class:`KeyError` was raised for a point without an assigned Olson timezone id (e.g. for Antarctica). Now this method returns None for such requests. :param location: The coordinates for which you want a timezone. :type location: :class:`geopy.point.Point`, list or tuple of (latitude, longitude), or string as "%(latitude)s, %(longitude)s" :param at_time: The time at which you want the timezone of this location. This is optional, and defaults to the time that the function is called in UTC. Timezone-aware datetimes are correctly handled and naive datetimes are silently treated as UTC. .. versionchanged:: 1.18.0 Previously this parameter accepted raw unix timestamp as int or float. This is now deprecated in favor of datetimes and support for numbers will be removed in geopy 2.0. :type at_time: :class:`datetime.datetime` or None :param int timeout: Time, in seconds, to wait for the geocoding service to respond before raising a :class:`geopy.exc.GeocoderTimedOut` exception. Set this only if you wish to override, on this call only, the value set during the geocoder's initialization. :rtype: ``None`` or pytz timezone. See :func:`pytz.timezone`. """


        warnings.warn('%(cls)s.timezone method is deprecated in favor of '
                      '%(cls)s.reverse_timezone, which returns geopy.Timezone '
                      'object containing pytz timezone and a raw response '
                      'instead of just pytz timezone. This method will '
                      'be removed in geopy 2.0.' % dict(cls=type(self).__name__),
                      DeprecationWarning, stacklevel=2)
        timezone = self.reverse_timezone(location, at_time, timeout)
        if timezone is None:
            return None
        return timezone.pytz_timezone