Syntax error on return statement

<?php 
function user_exists($username) { 
    $username = sanitize($username);
    $query = mysqli_query($connect, "SELECT COUNT(`user_id`) FROM `users` WHERE `username` = '$username'");
    return (mysqli_result($query, === 0) 1) ? true : false;
} ?>

PHP Parse error:

syntax error, unexpected ‘===’ (T_IS_IDENTICAL) in function on line 6

<?php
return mysqli_result($query) === 0 ? false : true;
?>

https://stackoverflow.com/questions/17239090/syntax-error-on-return-statement