How to require fbjs/lib/keyOf

I’m attempting to write a custom React event plugin, and I need to import some definitions from React. I’ve discovered that I can use React.require() for some symbols:

var SyntheticEvent = React.require('react/lib/SyntheticEvent');

However, this doesn’t work for keyOf:

var keyOf = React.require('fbjs/lib/keyOf');

It says it can’t find a module with that name.

Note that I’m just using the standard ‘react’ package, I’m not using any NPMs or exotic stuff.

(BTW if you are wondering what I am trying to accomplish, I’ve written a custom event plugin for polymer events, so that I will be able to use attributes like onTap="this.handleTap" in my react components.)