def LoadZipFile(self, zipfilename):
    """Convenience method to load zip file.

    Just a convenience method to load the zip file from the data store. This is
    useful if we ever want to change data stores and also as a means of
    dependency injection for testing. This method will look at our file cache
    first, and then load and cache the file if there's a cache miss

    Args:
      zipfilename: the name of the zip file to load

    Returns:
      The zip file requested, or None if there is an I/O error
    """
    zip_archive = None
    zip_archive = self.zipfile_cache.get(zipfilename)
    if zip_archive is None:
      try:
        zip_archive = zipfile.ZipFile(zipfilename)
        self.zipfile_cache[zipfilename] = zip_archive
      except (IOError, __HOLE__), err:
        logging.error('Can\'t open zipfile %s, cause: %s' % (zipfilename,
                                                             err))
    return zip_archive
dataset/ETHPy150Open aehlke/manabi/apps/dojango/appengine/memcache_zipserve.py/MemcachedZipHandler.LoadZipFile