https://airflow.apache.org/docs/apache-airflow/stable/configurations-ref.html#store-dag-code

![Captura de pantalla 2021-05-26 a las 17 47 56](https://user-images.githubusercontent.com/11339132/119691160-a2049a00-be4a-11eb-8f55-0ad2c6117620.png)

The Default is True or None?
tests/core/test_configuration.py
assert 'key4_result' == test_conf.get('test', 'key4')
        assert 'value6' == test_conf.get('another', 'key6')
        assert 'hello' == test_conf.get('test', 'key1', fallback='fb')
        assert 'value6' == test_conf.get('another', 'key6', fallback='fb')
        assert 'fb' == test_conf.get('another', 'key7', fallback='fb')
        assert test_conf.getboolean('another', 'key8_boolean', fallback='True') is True
        assert 10 == test_conf.getint('another', 'key8_int', fallback='10')
        assert 1.0 == test_conf.getfloat('another', 'key8_float', fallback='1')
        assert test_conf.has_option('test', 'key1')
        assert test_conf.has_option('test', 'key2')
        assert test_conf.has_option('test', 'key3')
        assert test_conf.has_option('test', 'key4')
        assert not test_conf.has_option('test', 'key5')
        assert test_conf.has_option('another', 'key6')
        cfg_dict = test_conf.as_dict(display_sensitive=True)
        assert 'cmd_result' == cfg_dict['test']['key2']
        assert 'key2_cmd' not in cfg_dict['test']
        
        
        cfg_dict = test_conf.as_dict(include_cmds=False, display_sensitive=True)
        assert 'key4' not in cfg_dict['test']
        assert 'printf key4_result' == cfg_dict['test']['key4_cmd']
    @mock.patch("airflow.providers.hashicorp._internal_client.vault_client.hvac")
    @conf_vars(
        {
            ("secrets", "backend"): "airflow.providers.hashicorp.secrets.vault.VaultBackend",
            ("secrets", "backend_kwargs"): '{"url": "http://127.0.0.1:8200", "token": "token"}',
        }
    )
    def test_config_from_secret_backend(self, mock_hvac):