Code works but Codecademy does not accept it

On this assignment: Strings and conditionals 1

Check if word contains letter. If it does -print True. If not - print False.
This is my code. It works as requested. What have I done wrong?

def letter_check(word, letter):
  for index in word:
    if index == letter:
  return print(False)

letter_check("strawberry", "a")

The instructions specify:

This function should return True if the word contains the letter and False if it does not.

The instructions aren’t asking for print statements.