utils.py 文件源码

def get_client_class(api_name, version, version_map):
    try:
        client_path = version_map[str(version)]
    except (KeyError, ValueError):
        msg = "Invalid %s client version '%s'. must be one of: %s" % (
              (api_name, version, ', '.join(version_map.keys())))
        raise exceptions.UnsupportedVersion(msg)

    return importutils.import_class(client_path)