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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 GetEventTags(self):
 """Retrieves the event tags. Yields: EventTag: event tag. """

    for event_tag in self._GetAttributeContainers(
        self._CONTAINER_TYPE_EVENT_TAG):
      event_identifier = identifiers.SQLTableIdentifier(
          self._CONTAINER_TYPE_EVENT, event_tag.event_row_identifier)
      event_tag.SetEventIdentifier(event_identifier)

      del event_tag.event_row_identifier

      yield event_tag