scan-for-emails.py

import re
import string
import sys

patterns = []

def load_patterns():
   f = open('patterns.txt')
   for line in f:
      i, o = line.split()
      patterns.append([re.compile(i, re.IGNORECASE), o])

load_patterns()

for line in sys.stdin:
   for p in patterns:
      m = p[0].search(line)
      if m:
         print p[1] % m.groups()