def __init__(self, app_yaml_path, backend_yaml_path):
    self._update_lock = threading.RLock()
    self._base_server_configuration = ServerConfiguration(app_yaml_path)
    backend_info_external = self._parse_configuration(
        backend_yaml_path)

    self._backends_name_to_backend_entry = {}
    for backend in backend_info_external.backends or []:
      self._backends_name_to_backend_entry[backend.name] = backend
    self._changes = dict(
        (backend_name, set())
        for backend_name in self._backends_name_to_backend_entry)
Initializer for BackendsConfiguration.
dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/tools/devappserver2/application_configuration.py/BackendsConfiguration.__init__