Now the `prime_factor()` doesn't return full information about the primes, as you don't know the multiplicity. Previously, it was simply repeated in the `primes` structure. Since we now have `prime_factor_multiplicities()` that report the multiplicities using a dictionary, don't you think that maybe the `prime_factor()` should return all the primes as it used to, so that you can simply multiply them out and get the original number `n`?