Comment 1 for bug 1843791

This is an interesting idea and I would like to get here eventually.

The sticking point, as you've found out, is that the canonical version of the Beautiful Soup code uses Python 2, and it's automatically converted to Python 3. I don't see a way to add these annotations without permanently switching to Python 3.

Because Beautiful Soup is frequently used in duct-tape environments I'm going to keep Python 2 support past the official end-of-life date, but eventually I will drop it, and we can pick up this issue then.