code: function assignKey(key, scope, method){
      var keys, mods;
      keys = getKeys(key);
      if (method === undefined) {
        method = scope;
        scope = 'all';
      }
  
      // for each shortcut
      for (var i = 0; i < keys.length; i++) {
        // set modifier keys if any
        mods = [];
        key = keys[i].split('+');
        if (key.length > 1){
          mods = getMods(key);
          key = [key[key.length-1]];
        }
        // convert to keycode and...
        key = key[0]
        key = code(key);
        // ...store handler
        if (!(key in _handlers)) _handlers[key] = [];
        _handlers[key].push({ shortcut: keys[i], scope: scope, method: method, key: keys[i], mods: mods });
      }
    }
docs: parse and assign shortcut