120-160 IP-addresses per minute without significant server load
(checking each against 58 DNSBLs; max_workers = 60)
The script is trying to fetch active DNSBLs from following resource:
http://www.dnsbl.info/dnsbl-list.php
You can specify additional / fallback set of DNSBLs in the top of script.
$ python dnsbl.py -i /path/to/hosts_file
$ python dnsbl.py -i 192.30.253.112 192.30.253.113
$ python dnsbl.py -i 192.30.253.0/24, 192.30.253.0/23 -o output.txt
BASE_LISTS = [...] -------> additional / fallback DNSBLs list
max_workers = 60 -------> max threads
verbose = False -------> logging
log_file = 'dnsbl.log' -------> log file