def get_zoneinfo():
 global zoneinfo
 if (zoneinfo is None):
  zoneinfo = zipfile.ZipFile(zoneinfo_path)
 return zoneinfo

def get_zoneinfo ( ) : global zoneinfo if ( zoneinfo is None ) : zoneinfo = zipfile . ZipFile ( zoneinfo_path ) return zoneinfo
cache the opened zipfile in the module .