Fix text concat

[Chubbly]

Fixes issue mentioned in #26. I have no idea why this fixes it, my Python knowledge is near zero.

[WingTangWong]

@Chubbly interesting. So looks like in the original, the return statement returns concat as a String. The change you made has it return a tuple where the first element is a String. If this is what makes it work then whatever is calling it was expecting some kind of iterable array or tuple? Just thinking aloud.