Greetings, Some time ago, I proposed adding a `.fromisocalendar` alternate constructor to `datetime` (bpo-36004 <https://bugs.python.org/issue36004>), with a corresponding implementation (PR #11888 <https://github.com/python/cpython/pull/11888>). I advertised it on datetime-SIG some time ago but haven't seen much discussion there, so I'd like to bring it to python-dev's attention as we near the cut-off for new Python 3.8 features. Other than the fact that I've needed this functionality in the past, I also think a good general principle for the datetime module is that when a class (time, date, datetime) has a "serialization" method (.strftime, .timestamp, .isoformat, .isocalendar, etc), there should be a corresponding /deserialization/ method (.strptime, .fromtimestamp, .fromisoformat) that constructs a datetime from the output. Now that `fromisoformat` was introduced in Python 3.7, I think `isocalendar` is the only remaining method without an inverse. Do people agree with this principle? Should we add the `fromisocalendar` method? Thanks, Paul