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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 AddComment(self, comment):
 """Adds a comment to the event tag. Args: comment (str):
 comment. """

    if not comment:
      return

    if not self.comment:
      self.comment = comment
    else:
      self.comment = ''.join([self.comment, comment])