useRef in functional component

useRefInFuncCompo.js

import React, { useRef } from "react";

const CustomTextInput = () => {
   const textInput = useRef();
   focusTextInput = () => textInput.current.focus();
      return (
         <>
           <input type="text" ref={textInput} />
           <button onClick={focusTextInput}>Focus the text input</button>
        </>
    );
}