> Would it be viable to rephrase the existing section in a manner that explains the functional purpose of NotImplemented without revolving around its use case in binary special methods?

To expand further upon this, here's an initial idea for improving the first sentence:

A special value used to indicate that an operation is not supported between specific types.

The section regarding it's usage in binary special methods could potentially remain. I'm thinking the main issue here (if there is one) is that the NotImplemented constant is defined _exclusively_ from a specific use case, rather than its general purpose.