How to convert a MAC number to MAC string?

Question

I want to convert a MAC address 00163e2fbab7 (stored as a string) to its string representation 00:16:3e:2f:ba:b7. What is the easiest way to do this?

Answer 1

Use a completely circuitous method to take advantage of an existing function that groups two hex characters at a time:

>>> ':'.join(s.encode('hex') for s in '00163e2fbab7'.decode('hex'))
'00:16:3e:2f:ba:b7'

Updated for Python 3:

>>> ':'.join(format(s, '02x') for s in bytes.fromhex('00163e2fbab7'))
'00:16:3e:2f:ba:b7'

Answer 2

Using the grouper idiom zip(*[iter(s)]*n):

In [32]: addr = '00163e2fbab7'

In [33]: ':'.join(''.join(pair) for pair in zip(*[iter(addr)]*2))
Out[33]: '00:16:3e:2f:ba:b7'

Also possible, (and, in fact, a bit quicker):

In [36]: ':'.join(addr[i:i+2] for i in range(0,len(addr),2))
Out[36]: '00:16:3e:2f:ba:b7'

Answer 3

If you have a string s that you want to join with colons, this should do the trick.

':'.join([s[i]+s[i+1] for i in range(0,12,2)])

Answer 4

If you are addicted to regular expressions you could try this unpythonic approach:

>>> import re
>>> s = '00163e2fbab7'
>>> ':'.join(re.findall('..', s))
'00:16:3e:2f:ba:b7'