Note that in Vyper (John Skaller's Python variant) these are legit integer
literals:
0b11111111 0B11111111
0o777 0O777
0d999 0D999
0xfFf 0XFFf
Vyper's octal notation is still ugly, but whoever first thought
0777 != 777
was a "good idea" was certifiably insane <0.25 wink>.