Match and extract if found

[DeaD_EyE]

44.44.44.44.11 is not a Valid IP-Address. A valid IPv4Address consists of 4 blocks with numbers from 0 to 255.
The problem is, that you want to recognize IPv6Addresses to filter them out and accepting IPv4Addresses and treating invalid data as IPv4-Adrdresses?

from contextlib import suppress
from ipaddress import IPv6Address, ip_address


def make_ipv4_set(file_like):
    results = set()

    for line in map(str.strip, file_like):

        addr = None
        with suppress(ValueError):
            addr = ip_address(line)

        if isinstance(addr, IPv6Address):
            continue

        results.add(line)

    return results


with (
    open("ip1_file.txt") as ip1_file,
    open("ip2_file.txt") as ip2_file,
):
    ip1_set = make_ipv4_set(ip1_file)
    ip2_set = make_ipv4_set(ip2_file)


results = ip1_set - ip2_set

for ip in results:
    print(ip)

Output:
44.44.44.44.11
192.168.0.6
192.168.0.4
192.168.0.1
192.168.0.2

Maybe I should take money for it....