TELNET RANGE EXTRACTOR/RANGE LIST MAKER [UPDATED may 5th]

import sys
import re

def validate_ip(ip_str):
    reg = r"^(([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.){3}([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])$"
    if re.match(reg, ip_str):
        return True
    else:
        return False

# range extractor coded by Freak
if len(sys.argv) != 3:
    print("Usage: " + sys.argv[0] + " list.txt ranges.txt")
fh = open(sys.argv[1], "rb")
out = open(sys.argv[2], "wb")
lines = fh.read().replace("\r", "").split("\n")
fh.close()
ranges = []
for line in lines:
    range = ".".join(line.split(".")[:2])+".0.0/16"
    if not validate_ip(range.split("/")[0]):
        continue
    if range not in ranges:
        ranges.append(range)
print("found " + str(len(ranges))) + " ranges to scan.")
out.write("\n".join(ranges))
out.close()