When calling a Go function that returns multiple values that aren't errors, store it in a tuple

[Keithcat1]

Because I was trying to wrap github.com/faiface/beep/vorbis so I can play audio, but the only useful function in that package returns (Streamer, Format, err), and because it returns too many values, Gopy refuses to add it in and I am seemingly stuck. There should be no problem simply returning a tuple. There are also some methods that return multiple values none of which are errors. If Gopy finds a function that returns an error but doesn't do so using the last return value, it should throw a compile error, but I've never seen one of those.