Fix Python – How do you express binary literals in Python?

How do you express an integer as a binary number with Python literals?
I was easily able to find the answer for hex:
>>> 0x12AF
4783
>>> 0x100
256

and octal:
>>> 01267
695
>>> 0100
64

How do you use literals to express binary in Python?

Summary of Answers

Python 2.5 and earlier: can express binary using int(‘01010101111’,2) but not with a lite….