Show all the possible combinations in a Ceasar encripture

CeasarBruteforce.py

def decypher(word):
    des = ''
    pos = 0
    for c in range(0, 26):
        for i in word:
            if ord(i.upper()) + c > 90:
                pos = 64
                aux = ord(i.upper()) + c - 90
                des += chr(pos + aux)
            else:
                pos = ord(i)
                des += chr(pos + c)
        print(des, f'- key = {c}')
        des = ''

word = str(input('Insert the word to shift in all possible ways: '))

decypher(word)