Racket Language:

Write a recursive Racket function to do the following:

Check if a list has duplicate values.

The function should work on all types of lists (not just simple lists of atoms).

Test cases:

(duplicates '( 1 5 6 7 8 3 2 3 )) //returns true

(duplicates '( cat bird pony dog frog )) //returns false

(duplicates '( a ( a b ) ( c ( b c )) ( a b )) //returns true

(duplicates '(( a ) ( a b ) ( c ( b c )) a b )) //returns false

(duplicates '( 1 )) //returns false