`logging.getLevelName()` can take either an `int` and returns a `str` or
a `str` and returns an `int` when the level name (`str`) or level
(`int`) is one of the registered log levels. If the value passed in
isn't one of the registered log levels, it returns the string `"level
%s" % lvl` where `lvl` is the value passed in to the function.
