from rt import *
######################Problem 3###########################
def sort_letters_backward(word):
    """prec: word is a lower-case string
    postc: returns a string with the letters in word sorted in reverse 
    alphabetical order
    """
    return "".join(reversed(sorted(word)))
def sort_letters_backward(word):
    w = list(word)
    w.sort()
    backwards = reversed(w)
    return "".join(backwards)
def sort_letters_backward(word):
    w = list(word)
    w.sort(reverse=True)
    return "".join(w)
def main():
    print("*************** Problem 3 Tests **************")
    run_test(sort_letters_backward, "rmmhea", ["hammer"])
main()