Python literals preceded by '0' tells it to express in in octal. literals preceded by '0x' are hexadecimal. literals preceded by '0b' are binary.
print 0010
8
print 0b110011
51
print 0x100
256
I have also tested the '0o' on my python 2.7.6 and gotten
print 0o111 # number 0 letter o followed by digits
73
Note that Python 3 will print 0111 as 111 as it is supposed to treat a leading 0 as part of the decimal number unless it is followed by 'x', 'o', or 'b' I do not have Python 3 so I cannot test this myself.
Thanks to @AdamSmith for pointing this out in his comment.