evil-mode: python surround string with function

I've just started exploring evil-mode and was wondering about the behaviour of the evil-surround package when it comes to surrounding lines with functions. For example, if I have some string that I've written "Hello world!" and I want to surround it with a "print" function, I thought I'd be able to do =yssfprint<RET>=, but I wind up getting the following: print( "Hello world!") I'm not sure if it's because =yss= selects the linebreak before the quotation mark or quite what's going on. Would someone be so kind as to elucidate the situation for a real vim/evil-mode newbie?