def METHOD_NAME(self, m):
    m.return_value = {
        "key": {
            "enabled": True,
            "url": "my_url",
            "geo_ref": {
                "url": "my_geo_ref_url",
                "drop_variables": ["bathymetry"],
            },
            "climatology": "my_climatology",
            "name": "my_name",
            "help": "my_help",
            "quantum": "my_quantum",
            "type": "my_type",
            "grid_angle_file_url": "my_grid_angle_file_url",
            "bathymetry_file_url": "my_bathy_file_url.nc",
            "model_class": "my_model_class",
            "time_dim_units": "my_time_units",
            "attribution": "my_<b>attribution</b>",
            "cache": "123",
            "lat_var_key": "my_lat",
            "lon_var_key": "my_lon",
            "variables": {
                "var": {
                    "name": "my_variable",
                }
            },
        }
    }
    assert len(DatasetConfig.get_datasets()) == 1
    result = DatasetConfig("key")
    assert result.url == "my_url"
    assert result.geo_ref["url"] == "my_geo_ref_url"
    assert result.geo_ref["drop_variables"] == ["bathymetry"]
    assert result.key == "key"
    assert result.climatology == "my_climatology"
    assert result.name == "my_name"
    assert result.help == "my_help"
    assert result.quantum == "my_quantum"
    assert result.grid_angle_file_url == "my_grid_angle_file_url"
    assert result.bathymetry_file_url == "my_bathy_file_url.nc"
    assert result.model_class == "my_model_class"
    assert result.type == "my_type"
    assert result.time_dim_units == "my_time_units"
    assert result.lat_var_key == "my_lat"
    assert result.lon_var_key == "my_lon"
    assert result.attribution == "my_attribution"
    assert result.cache == 123
    assert not result.variable[Mock(key="var")].is_hidden