Reads file with networks(CIDR or range format) and generates list of IP addresses, contained in this networks.

gen_ip_list.py

import ipaddress
import re


firstIP_pattern = re.compile('^(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)')
lastIP_pattern = re.compile('(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$')
CIDR_pattern = re.compile('^(([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.){3}([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])(\/([0-9]|[1-2][0-9]|3[0-2]))$')



with open('networks.txt', 'r') as file, open('ip_list.txt', 'w+') as result_file:
    for line in file:
        print line
        line = line.strip('\n')
        line = line.strip() 
        if not firstIP_pattern.match(line):
            continue
        if CIDR_pattern.match(line):
            cidr_net = ipaddress.ip_network(unicode(line, 'utf-8'))
            for ip in cidr_net:
                result_file.write(str(ip) + '\n')
        else:
            first_IPv4 = ipaddress.IPv4Address(unicode(firstIP_pattern.search(line).group(0), 'utf-8'))
            last_IPv4 =  ipaddress.IPv4Address(unicode(lastIP_pattern.search(line).group(0), 'utf-8'))
            for net in ipaddress.summarize_address_range(first_IPv4, last_IPv4):
                for ip in net:
                    result_file.write(str(ip) + '\n')