Method find

crates/vm/src/builtins/str.rs:1191–1194

(&self, args: FindArgs)

    #[pymethod]
    fn find(&self, args: FindArgs) -> isize {
        self._find(args, |r, s| Some(Self::_to_char_idx(r, r.find(s)?)))
            .map_or(-1, |v| v as isize)
    }

    #[pymethod]
    fn rfind(&self, args: FindArgs) -> isize {