<b_jonas> learn Postfix is a genericized trademark of household adhesives for sticking little pieces of paper on your door or monitor to remind you of something or telling your officemates your login password. Called Tack-it in the U.S.

#!/usr/bin/env python
import sys
import json
data = json.loads(sys.stdin.read().decode('utf-8'))
print eval(sys.argv[1]).encode('utf-8')