ineffective, because in bottom-up mode the directories in *dirnames* are
generated before *dirpath* itself is generated.
- By default errors from the :func:`listdir` call are ignored. If optional
+ By default errors from the :func:`listdir` call are ignored. If optional
argument *onerror* is specified, it should be a function; it will be called with
one argument, an :exc:`OSError` instance. It can report the error to continue
with the walk, or raise the exception to abort the walk. Note that the filename