re Python3
import re
>>> m = re.search('(?<=abc)def', 'abcdef')
>>> m.group(0)
'def'
Proud Penguin
import re
>>> m = re.search('(?<=abc)def', 'abcdef')
>>> m.group(0)
'def'
>>> p = re.compile('(a(b)c)d')
>>> m = p.match('abcd')
>>> m.group(0)
'abcd'
>>> m.group(1)
'abc'
>>> m.group(2)
'b'