Currently the “datetime” documentation has quick descriptions of classes marked up with “.. class::” in the introduction, and then dedicated sections with more details. Many other parts of Python’s documentation have a similar structure.

IMO it is better to include the “.. class::” markup closer to the list of methods, and then each method can be indented underneath it. See my changes to the “socketserver” documentation (Issue 15608, compare 3.4 vs 3.5) where I indented a whole lot of methods under class definitions. I suspect the reason why things are not like this is just that it is leftover from a conversion from an earlier markup format.

The earlier class introductions are also marked up with :noindex:, which would explain which become link targets.

Dunno about your intersphinx stuff though. Is that linking to the Python documentation from external projects?