Change Details

> I noticed that navigation in PyCharm/VS Code did not work for nodes variable. I think this is frustrating, especially for newcomers. This will make python IDEs work better with the test framework. Our code already switched to python 3.6 types hints for `chain` and `setup_clean_chain`, so the only change for these attributes is to remove `Optional`. This is a backport of core#20954

> I noticed that navigation in PyCharm/VS Code did not work for nodes variable. I think this is frustrating, especially for newcomers. This will make python IDEs work better with the test framework. Our code already switched to python 3.6 types hints for `chain` and `setup_clean_chain`, so the only change for these attributes is to remove `Optional`. This is a backport of [[https://github.com/bitcoin/bitcoin/pull/20954 | core#20954]]

> I noticed that navigation in PyCharm/VS Code did not work for nodes variable. I think this is frustrating, especially for newcomers. This will make python IDEs work better with the test framework. Our code already switched to python 3.6 types hints for `chain` and `setup_clean_chain`, so the only change for these attributes is to remove `Optional`. This is a backport of [[https://github.com/bitcoin/bitcoin/pull/20954 | core#20954]]