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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 GetYearFromPosixTime(posix_time, timezone=pytz.UTC):
 """Gets the year from a POSIX timestamp The POSIX time is the number of seconds since 1970-01-01 00:00:00 UTC. Args: posix_time: An integer containing the number of seconds since 1970-01-01 00:00:00 UTC. timezone: Optional timezone of the POSIX timestamp. Returns: The year of the POSIX timestamp. Raises: ValueError: If the posix timestamp is out of the range of supported values. """

  datetime_object = datetime.datetime.fromtimestamp(posix_time, tz=timezone)
  return datetime_object.year