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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 Parse(self, stat, knowledge_base):
 """Convert the timezone to Olson format."""

    _ = knowledge_base
    value = stat.registry_data.GetValue()
    result = ZONE_LIST.get(value.strip())
    if not result:
      yield rdfvalue.RDFString("Unknown (%s)" % value.strip())

    yield rdfvalue.RDFString(result)