Function _warn

Lib/idlelib/config.py:772–779

(msg, *key)

_warned = set()
def _warn(msg, *key):
    key = (msg,) + key
    if key not in _warned:
        try:
            print(msg, file=sys.stderr)
        except OSError:
            pass
        _warned.add(key)


class ConfigChanges(dict):