personal firewall software is blocking the connection

[vsoler]

I'am getting this annoying message all the time when using IDLE.

...  personal firewall software is blocking the connection

When I am editing a source *.py file and I click on F5 (run) I get the
above message.

What can I do?

I am using Norton Internet Security. I try to find if 127.0.0.1 is
blocked, but I do not know where to look.

Can anybody help?