Write PropTypes.* or import bool, string, etc?

```js
import { bool, string } from 'prop-types'

Component.propTypes = {
  loading: bool.isRequired,
  name: string.isRequired
}

// or current method:

import PropTypes from 'prop-types'

Component.propTypes = {
  loading: PropTypes.bool.isRequired,
  name: PropTypes.string.isRequired
}
```