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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 SetTimeZone(self, time_zone):
 """Sets the time zone. Args: time_zone (str):
 time zone. Raises: ValueError: if the timezone is not supported. """

    try:
      self._time_zone = pytz.timezone(time_zone)
    except (AttributeError, pytz.UnknownTimeZoneError):
      raise ValueError('Unsupported timezone: {0!s}'.format(time_zone))