alist-get
alist-get is a compiled Lisp function in `subr.el
'.
(alist-get KEY ALIST &optional DEFAULT REMOVE)
Get the value associated to KEY in ALIST.
DEFAULT is the value to return if KEY is not found in ALIST.
REMOVE, if non-nil, means that when setting this element, we should
remove the entry if the new value is `eql' to DEFAULT.