docs: def _GetAllShowList(self):
      """
      Populates self._allShowList with the epguides all show info.
  
      On the first lookup for a day the information will be loaded from
      the epguides url. This will be saved to local file _epguides_YYYYMMDD.csv
      and any old files will be removed. Subsequent accesses for the same day
      will read this file.
      """
      today = datetime.date.today().strftime("%Y%m%d")
      saveFile = '_epguides_' + today + '.csv'
      saveFilePath = os.path.join(self._saveDir, saveFile)
      if os.path.exists(saveFilePath):
        # Load data previous saved to file
        with open(saveFilePath, 'r') as allShowsFile:
          self._allShowList = allShowsFile.read()
      else:
        # Download new list from EPGUIDES and strip any leading or trailing whitespace
        self._allShowList = util.WebLookup(self.ALLSHOW_IDLIST_URL).strip()
  
        if self._ParseShowList(checkOnly=True):
          # Save to file to avoid multiple url requests in same day
          with open(saveFilePath, 'w') as allShowsFile:
            goodlogging.Log.Info("EPGUIDE", "Adding new EPGUIDES file: {0}".format(saveFilePath), verbosity=self.logVerbosity)
            allShowsFile.write(self._allShowList)
  
          # Delete old copies of this file
          globPattern = '_epguides_????????.csv'
          globFilePath = os.path.join(self._saveDir, globPattern)
          for filePath in glob.glob(globFilePath):
            if filePath != saveFilePath:
              goodlogging.Log.Info("EPGUIDE", "Removing old EPGUIDES file: {0}".format(filePath), verbosity=self.logVerbosity)
              os.remove(filePath)