Definitely not downvoting - but, all the extra parentheses are a kind of lispy in having to grok (and balance). Also, having the (str) at the beginning makes m

Definitely not downvoting - but, all the extra parentheses are a kind of lispy in having to grok (and balance). Also, having the (str) at the beginning makes me think that it's an input, whereas having -> makes it clear (to me at least) that it's an output return type.