assoc
builtin-function
(assoc item alist &key key test)
Returns the first Cons item in association list alist with a car matching
item.
make-html > (assoc 'a '((b c) (a d) (e f)))
it: (a d)
make-html > (assoc 3 '(("bbb" c) ("a" d) ("e" f)) :key length)
it: ("bbb" c)