[docs] [issue17188] Document 'from None' in raise statement doc.

Terry J. Reedy added the comment: New changeset 763557eac06ba60d7c5133e4f80df8870d8f917e by terryjreedy (csabella) in branch 'master': bpo-17188: DOC: Document 'from None' in raise statement (#1671) https://github.com/python/cpython/commit/763557eac06ba60d7c5133e4f80df8870d8... ---------- _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue17188> _______________________________________