Overriding the save() method for a Django model to dynamically obtain the hostname and IP addresses for a URL if none were given

models.py

from socket import getaddrinfo
from socket import IPPROTO_TCP  # pylint: disable=no-name-in-module

    def save(self, *args, **kwargs):
        """Override save."""
        if self.url:
            if not self.hostname:
                self.hostname = urlparse(self.url).hostname
        if self.hostname:
            if not self.ip_addrs:
                # Use socket to get all the IP addresses using a fictional connection to tcp/443
                # No connection is actually made
                _ = getaddrinfo(self.hostname, 443, proto=IPPROTO_TCP)
                ip_addrs = [x[4][0] for x in _]
                self.ip_addrs = ip_addrs
        super().save(*args, **kwargs)