FR: Add Link to Typing RTD in `typing` Module

[adam-grant-hendry]

Feature or enhancement

Discussions on adding a link to the typing readthedocs (RTD) on the typing module documentation page have been had:

• python/typing: Make Link to ReadTheDocs Typing Docs More Explicit
• python/typing: Why is typeshed information not integrated into the official python docs?
• python/cpython: Proposal: Convert the typing-module PEPs into a series of HOWTOs
• python/typing: Document Structure and Wishlist

The request is to add a link to the top of the typing module docs linking readers to the page. This would serve the following needs:

1. The RTD is not particularly discoverable via search engines (the most notable link is in the README of the typeshed repo)
2. A desire has been expressed for incorporating PEPs into a series of HOWTOs and some consensus has been achieved that the RTD would be the best place for this

Pitch

Please add a link to the typing readthedocs on the python typing module docs page.

• It has been suggested that a "See Also" box would work nicely

The OP is open to any implementation resulting in an easily findable and noticeable hyperlink for users.

Previous discussion

Repeated from above:

• python/typing: Make Link to ReadTheDocs Typing Docs More Explicit
• python/typing: Why is typeshed information not integrated into the official python docs?
• python/cpython: Proposal: Convert the typing-module PEPs into a series of HOWTOs
• python/typing: Document Structure and Wishlist

[AlexWaygood]

The link has been added, and the change has been backported to 3.11 and 3.10.