io.open() is an alias for open() on Python 3.

__ne__() defaults to the opposite of __eq__() on Python 3
when it doesn't return NotImplemented.

Thanks Tim Graham for the review.

Thanks Tim Graham and Simon Charette for the reviews.

Thanks Tim Graham for the review.

Per deprecation timeline. Refs ed0ff913.

Per deprecation timeline.

Per deprecation timeline.

Per deprecation timeline.

Per deprecation timeline.