[3.10] bpo-46270: Describe the in and not in operators as membership tests. (GH-30504)#30509

rhettinger merged 1 commit intopython:3.10python/cpython:3.10from

miss-islington:backport-d24cd49-3.10miss-islington/cpython:backport-d24cd49-3.10Copy head branch name to clipboard