TypeError: __WEBPACK_IMPORTED_MODULE_0_react___default.a.createRef is not a function

I am new to React.js and just now i was learning the concept of ref in React. They have new createRef API in V16.3. I was trying to learn this from REACT DOC's like this -

import React from "react";

export class MyComponent extends React.Component {

constructor(props) {
    super(props);
    // create a ref to store the textInput DOM element
    this.textInput = React.createRef();
    this.focusTextInput = this.focusTextInput.bind(this);
}

focusTextInput() {
    // Explicitly focus the text input using the raw DOM API
    // Note: we're accessing "current" to get the DOM node
    this.textInput.current.focus();
}

render() {
    // tell React that we want to associate the <input> ref
    // with the `textInput` that we created in the constructor
    return (
        <div>
            <input
                type="text"
                ref={this.textInput} />

            <input
                type="button"
                value="Focus the text input"
                onClick={this.focusTextInput}
            />
        </div>
    );
}

}

And I was Getting this Error -

TypeError: __WEBPACK_IMPORTED_MODULE_0_react___default.a.createRef is not a function

Here is the screenshot -