code: function isFlat(object) {
    return isObject(object) && (isNull(Object.getPrototypeOf(object)) ||
                                isNull(Object.getPrototypeOf(
                                       Object.getPrototypeOf(object))));
  }
docs: Returns `true` if given `object` is flat (it is direct decedent of
  `Object.prototype` or `null`).
  @examples
  isFlat({}) // true
  isFlat(new Type()) // false