code: def open_resource(self, name):
          
          # Import nested here so we can run setup.py without GAE.
          from google.appengine.api import memcache
          from pytz import OLSON_VERSION
  
          name_parts = name.lstrip('/').split('/')
          if os.path.pardir in name_parts:
              raise ValueError('Bad path segment: %r' % os.path.pardir)
  
          cache_key = 'pytz.zoneinfo.%s.%s' % (OLSON_VERSION, name)
          zonedata = memcache.get(cache_key)
          if zonedata is None:
              zonedata = get_zoneinfo().read('zoneinfo/' + '/'.join(name_parts))
              memcache.add(cache_key, zonedata)
              log.info('Added timezone to memcache: %s' % cache_key)
          else:
              log.info('Loaded timezone from memcache: %s' % cache_key)
  
          return StringIO(zonedata)
docs: Opens a resource from the zoneinfo subdir for reading.