$ ./python -m timeit -s 'from os import urandom' 'urandom(1000000)'
10 loops, best of 3: 132 msec per loop
$ ./python -m timeit -s 'from random import getrandbits' 'n = 1000000; getrandbits(n*8).to_bytes(n, "little")'
100 loops, best of 3: 14.1 msec per loop

With the purposed method this can be up to 3.4 times faster, but as I said in issue27072, I don't think API growing is worth the benefit.