document minimum required python versions
It looks like at least sometimes we end up using python constructs that require python >=2.7 or >= 3.1. (See #27675 (moved) for an example.) We should document this somewhere, possibly in doc/HACKING.
It looks like at least sometimes we end up using python constructs that require python >=2.7 or >= 3.1. (See #27675 (moved) for an example.) We should document this somewhere, possibly in doc/HACKING.