Return type for get_child_by_id and get_widget_by_id

[aaronst]

Loving the new get_child_by_id and get_widget_by_id methods! But I've noticed that Pylance gets real unhappy with the return type of Widget. For instance, if I get a Static and then call update. Is there any typing magic we can add to make this better, or is this something we'll just need to ignore?

[willmcgugan]

We should do something similar to query, where you pass on the type and it validates it at runtime and statically.

In the meantime try an assert isinstance(widget, MyWidget) to quell PyLance.

[aaronst]

I can make a PR for this!

[willmcgugan]

A PR would be amazing. 👍