Write the Racket function that begins

(define (enumerate L)

in which L is a list. The output should be a list identical to L, except that each element from the original input is now the second element of a sequentially numbered list, starting from 0.

Please code in Racket using #lang racket

Thank you

Hint: create a recursive helper function with more arguments than enumerate. Then, call the helper function with a reasonable default value!