Something
public text v1 · immutable>>> s = 'foobar'
>>> m = re.compile('foo(bar)').search(s)
>>> m
<_sre.SRE_Match object at 0x688a0>
>>> if m.group(1) != None:
... print m.group(1)
...
bar
>>> if m.group(3) != None:
... print m.group(3)
...
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
IndexError: no such group