background_loading page with errors in the "example class" paragraph

[background_loading / example class](https://github.com/godotengine/godot-docs/blob/a7d2ec2aaf2b24fae4b4428e99111e28b1965245/tutorials/io/background_loading.rst#example-class) does not work due to a mistake in the script.
resource_queue.gd has `VS.flush()` in line 81, which throws errors due to be unknown. `flush()` is only known to PCKPacker class, but replacing `VS` by `PCKPacker` doesn't works and throws errors. Also commenting the whole line 81 doesn't works, because the game freezes without errors in the editor.
Back to the doc page, there seems to be also an error in [the example](https://github.com/godotengine/godot-docs/blob/a7d2ec2aaf2b24fae4b4428e99111e28b1965245/tutorials/io/background_loading.rst#example-1). It should start with `var queue = preload("res://resource_queue.gd").new()`, but the `var` is missing. Also not sure about `pause_menu.show()` or if that should rather be `add_child(pause_menu)` instead.