code: function clone(obj) {
    if (Array.isArray(obj)) {
      return obj.map((val) => clone(val))
    }
    if (isPlainObj(obj)) {
      return Object.keys(obj).reduce((copy, key) => {
        copy[key] = clone(obj[key])
        return copy
      }, {})
    }
    return obj
  }
docs: Clone `obj`.
  https://github.com/component/clone/blob/master/index.js