Thank you for the answers. Anyway from what is written in the documentation it's not clear to me at all that the default expected behaviour is to forbid accesses not coming from 127.0.0.1: "runserver [optional port number, or ipaddr:port] Starts a lightweight development Web server on the local machine. By default, the server runs on port 8000 on the IP address 127.0.0.1. You can pass in an IP address and port number explicitly..."
In my experience just running a server on 127.0.0.1 doesn't imply you can't access it from other IPs. I think that explaining a bit more of this feature in official docs will prevent other newbies like me to spend lots of time in this pitfall. Cheers, Emanuele

