Maybe "unreadable" and "readable" aren't the best ways to approach this conversation.
It's certainly less readable than, say, my_str.strip()
It's certainly less readable than, say, my_str.strip()
The quotes don't function like the parens. If this were a two argument function, you wouldn't put one pair of quotes around the whole thing. They're clearly transforming the variable somehow, but I'm not sure how and/or why they're necessary.