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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 AddEventTags(self, event_tags):
 """Adds event tags. Args: event_tags (list[EventTag]):
 event tags. Raises: IOError: when the storage file is closed or read-only or if the event tags cannot be serialized. OSError: when the storage file is closed or read-only or if the event tags cannot be serialized. """

    self._RaiseIfNotWritable()

    for event_tag in event_tags:
      self.AddEventTag(event_tag)