Hi, I struggle with mocking a StackReference in python. This doesn't work:

class MyMocks(pulumi.runtime.Mocks):
        def new_resource(self, args: pulumi.runtime.MockResourceArgs):
            outputs = args.inputs
            if args.typ == "pulumi:pulumi/StackReference":
                outputs = {
                    **args.inputs,
                    "outputs": {"key": "value, "key2: "value2", "secret1": "secret_value1"},
                    "secret_output_names": ["secret1"],
                }
            return args.name + '_id', outputs

        def call(self, args: pulumi.runtime.MockCallArgs):
            return {}, None

It fails with:

>   value = Output.all(Output.from_input(name), self.outputs).apply(lambda l: l[1][l[0]]) # type: ignore
E   TypeError: 'NoneType' object is not subscriptable

../.venv/lib/python3.9/site-packages/pulumi/stack_reference.py:82: TypeError

Is there any example how to do it? 🙏