schema is not defined at Object../node_modules/js-schema/lib/schema.js

Install package
```npm install js-schema```

after in index.js
```js
import schema from 'js-schema';
// or
import * as schema from 'js-schema';
```
When i try run in 
```
schema is not defined at Object../node_modules/js-schema/lib/schema.js
```