Arbitrary length bytes to int builtin in Python

Question

I'm looking for a function that takes an arbitrary length bytes object, and converts it to an int. Obviously endianness is a required parameter to this function.

I'm certain I encountered a builtin on either bytes or int, but can't find it anymore. There are plenty of answers on similar questions involving use of struct, and manually enumerating the individual byte values. Is there a builtin that does this conversion without using C-like assumptions/modules?

def int(bytes, 'little') -> int

This isn't a duplicate because the other question is for 16-bit integers, and this is for arbitrary length integers. — amcnabb, Feb 01 '13 at 23:24
I agree this is not a duplicate, the accepted answer here http://stackoverflow.com/questions/30402743/python-2-7-equivalent-of-built-in-method-int-from-bytes appears to be relevant however — Dan, May 20 '16 at 18:14

score 18 · Accepted Answer · answered Mar 28 '11 at 02:58

18

Since 3.2:

>>> int.from_bytes(b'\xFF\x00','little')
255
>>> int.from_bytes(b'\xFF\x00','big')
65280

answered Mar 28 '11 at 02:58

Kabie

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It would be nice to have a python2 version, too. – amcnabb Feb 01 '13 at 23:25

Arbitrary length bytes to int builtin in Python

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