Write a JavaScript program to create a new string of 4 copies of the last 3 characters of a given original string. The length of the given string must be 3 and above

function newstring(str)
{
  if (str.length >= 3) {
    result_str = str.substring(str.length - 3);
    return result_str + result_str + result_str + result_str;
  }
  else
    return false;
}
console.log(newstring("Python 3.0"));
console.log(newstring("JS"));
console.log(newstring("JavaScript"));