Python URL splitting

I have a string like `google.com` in Python, which I would like split into two parts: `google` and `.com`. The problem is where I have a URL such as `subdomain.google.com`, which I would like to be split into `subdomain.google` and `.com`. How do I separate the rest of the URL from the TLD? It can't operate based on the last `.` in the URL because of TLDs such as `.co.uk`. Note the URL does not contain http:// or www.