define(function(){
    if (typeof global !== 'undefined' && typeof global !== 'function') {
        // global spec defines a reference to the global object called 'global'
        // https://github.com/tc39/proposal-global
        // `global` is also defined in NodeJS
        return global;
    }
    else if (typeof window !== 'undefined') {
        // window is defined in browsers
        return window;
    }
    else if (typeof self !== 'undefined') {
        // self is defined in WebWorkers
        return self;
    }
    return this;
});