Write a python program a program to print letters in descending order of character occurrence frequency like example "google" output should be g-2 ,0 -2 , l- 1, b-1

Write a program to receive strings and print letters in descending order of character occurrence frequency

love= input('enter a string ')
def rev(string):
    d = dict()
    for key in string:
        if key not in d:
            d[key] = 1
        else:
            d[key] += 1
    return d

print (rev(love))