import ipaddress as ip
CLASS_C_ADDR ='192.0.2.0'
if __name__ == '__main__':
    not_exit =True
    while not_exit:
        prefix = input('Enter the prefix length(24-30):')

        prefix =int(prefix)

        if prefix not in range(24,31):
            raise Exception('Prefix length must be between 24 and 30')

        net_addr = CLASS_C_ADDR+'/'+str(prefix)
        print('Using network address:',net_addr)
        net4= ip.ip_network(net_addr)
        print('This prefix will give',net4.num_addresses,'IP address')
        print('The network configuration will be')
        print('\t Network address:',str(net4.network_address))
        print('\t Subnet mask:',str(net4.netmask))
        print('\t Broadcast address:',str(net4.broadcast_address))
        first_ip,last_ip = list(net4.hosts())[0],list(net4.hosts())[-1]
        print('\t Host IP address:from',first_ip,'to',last_ip)
        if prefix < 30:
            all_subnets = list(net4.subnets())
            print('\t Largest Subnet information:')
            for s in all_subnets:
                print('\t\t',s)
        ok =input('Enter y to exit,or any key to continue [y/n]')
        ok =ok.lower()
        if ok.strip()=='y':
            not_exit = False