sid_rev.py

for line in open('a.txt'):
  # print line
  a_id = line.find("sid:")
  a_rev = line.find("rev:")
  # print a_id
  # print a_rev
  print line[a_id+4:a_rev-2]
  print line[a_rev+4:-3]

  for line in open('b.txt'):
    # print line
    b_id = line.find("sid:")
    b_rev = line.find("rev:")
    # print b_id
    # print b_rev
    print line[b_id+4:b_rev-2]
    print line[b_rev+4:-3]