regexp matching end of line or comma

[Jean-Michel Pichavant]

Hy guys,

I'm struggling matching patterns ending with a comma ',' or an end of 
line '$'.

import re

ex1 = 'sumthin,'
ex2 = 'sumthin'
m1 = re.match('(?P<something>\S+),', ex1)
m2 = re.match('(?P<something>\S+)$', ex2)
m3 = re.match('(?P<something>\S+)[,$]', ex1)
m4 = re.match('(?P<something>\S+)[,$]', ex2)

print m1, m2
print m3
print m4

<_sre.SRE_Match object at 0x8834de0> <_sre.SRE_Match object at 0x8834e20>
<_sre.SRE_Match object at 0x8834e60>
None

My problem is that m4 is None while I'd like it to match ex2.

Any clue ?

JM