Python: Regexes

from __future__ import print_function
import re

match = re.search(r'lac', 'The black cat climed')
if match:
    print("Matching")       # Matching
    print(match.group(0))   # lac

match = re.search(r'dog', 'The black cat climed')
if match:
    print("Matching")
else:
    print("Did NOT match")
    print(match)     # None

The search method returns an object or None, if it could not find any match. If there is a match you can call the group() method. Passing 0 to it will return the actual substring that was matched.