In collect_children(), put a try-except around os.waitpid() because it may raise an exception (when there are no children).  Reported by Andy Dustman.
In collect_children(), put a try-except around os.waitpid() because it
may raise an exception (when there are no children).  Reported by
Andy Dustman.

sk-/python2.7-type-annotator,sk-/python2.7-type-annotator,sk-/python2.7-type-annotator