Issue with `rx.foreach` for a computed var which is a `Union` of `str` and a `List[rx.Model]` type

[bamchip]

Describe the bug Error message: TypeError: You must provide an annotation for the state var _. Annotation cannot be typing.Any``

When a computed var is of type List[List[Union[str, List[Topics]]]] (where Topics is a rx.Model) rx.foreach fails to process the data.

To Reproduce Steps to reproduce the behavior:

• Code/Link to Repo:

# MyTopicsState(rx.State)

@rx.var
def get_topics(self) -> List[List[Union[str, List[Topics]]]]:
    # <code>
    # [["Parent Topic Name", [Topics(), Topics(), ...]], ["Parent Topic Name 2", [Topics(), Topics(), ...]], ...]
    return topics

# frontend

rx.foreach(
    MyTopicsState.get_topics,
    render_topics
),

def render_topics(topics: List[Union[str, List[Topics]]]):
    parent_topic_name: str = topics[0]
    sub_topics: List[Topics] = topics[1]
    return rx.box(
        rx.vstack(
            rx.text(parent_topic_name),
            rx.foreach(
                sub_topics,
                to_ui_topic
            ),
        ),
        width="100%",
    )

def to_ui_topic(topic: Topics):
    topic_name: str = topic.topic_name
    return rx.box(
        rx.text(topic_name),
        width="100%",
    )

Expected behavior A clear and concise description of what you expected to happen.

Screenshots If applicable, add screenshots to help explain your problem.

Specifics (please complete the following information):

• Python Version: 3.9
• Reflex Version: 0.2.0
• OS:
• Browser (Optional):

Additional context Add any other context about the problem here.

[bamchip]

If I create 2 different computed vars rx.var, one for each type in the Union it works as expected. So I believe the issue must be with the complex type.

[masenf]

BaseVar should support Union type now, please try again with 0.3.3 or newer and reopen if the issue persists.