// created by ChatGPT :)
function containsOnlyLetters(str) {
return /^[A-Za-z]+$/.test(str);
}
// Example usage
console.log(containsOnlyLetters("HelloWorld")); // true
console.log(containsOnlyLetters("Hello123")); // false
console.log(containsOnlyLetters("123")); // false
console.log(containsOnlyLetters("")); // false