See https://networkx.org/documentation/stable/reference/classes/generated/networkx.DiGraph.nodes.html

Specifically:

When called, if data is False, an iterator over nodes. Otherwise an iterator of 2-tuples (node, attribute value) where the attribute is specified in data. If data is True then the attribute becomes the entire data dictionary.

I was thinking something like the code in python/mypy#22199 would work to extract the value type!

(Sorry for so many networkx issues! I recently enabled it and ran across all of this. This one's the last one.)