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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 _GetShowID(self, showName):
 """ Get epguides show id for a given show name. Attempts to match the given show name against a show title in self._showTitleList and, if found, returns the corresponding index in self._showIDList. Parameters showName : string Show name to get show ID for. Returns int or None If a show id is found this will be returned, otherwise None is returned. """

    self._GetTitleList()
    self._GetIDList()

    for index, showTitle in enumerate(self._showTitleList):
      if showName == showTitle:
        return self._showIDList[index]
    return None