'Constructor.
All arguments should be specified as keyword arguments.
Args:
adapter: Optional AbstractAdapter subclass instance;
default IdentityAdapter.
config: Optional Configuration object.'

@_positional(1)
def __init__(self, adapter=None, config=None, _api_version=_DATASTORE_V3):

    super(Connection, self).__init__(adapter=adapter, config=config, _api_version=_api_version)
    self.__adapter = self.adapter
    self.__config = self.config
