The fact that the definition of class _() stayed in that forked code is quite funny.
It's also showing how hard it can be to maintain a good architecture even for simple code, because when you are not the one that made the code, you don't know the location of every piece of code, and you easily forget to remove some.

I really stared at that one for a minute before searching for the additionnal preloaded code !
So funny solution...

I tested it with that :

is_anagram('¡€•¡', '¡¡•€')

And it works. My code uses ord, and any character in unicode has a unique ord value. So I think it really works with the whole unicode.