New to python/coding Need help on Understanding why this code isn't working. Thanks!

[mat3372]

code that the(interpreter/compiler **not sure which ones right) don't like

What that does mean exactly? Do you get error?
There are several odd things in the code that you should be aware - using mutable default arguments and also you return string, not list

I didn't know name of what ran the code(compiler/ interpreter **Don't know if either is right)
Yes I do get 1 error and it has squiggly line underneath "def alphabetize" on first line. When I hover over it, it says...Dangerous default value [] as argument.