docs for 2.7.0 https://pygithub.readthedocs.io/en/v2.7.0/apis.html
docs for 2.8.0 https://pygithub.readthedocs.io/en/v2.8.0/apis.html

grep "github.Repository.Repository.get_pulls()"

In the 2.7.0 page, the grepped text links to the docs for the Repository object.

In the 2.8.0 page, there is no link.

Similarly, the 2.7.0 docs have a lot to say about the members of Repository, but the 2.8.0 docs show no members at all.