Simple Python Http Server & Firewall

[soniabu]

Hi everyone.
Simple Python Server works correctly if I turn off the Firewall on the PC from which I make the files available (while on the LAN PC I can leave it on).
If, on the other hand, the Firewall is turned on in the PC-Server (despite having inserted an extra port 8000, TCP) it does not allow entry and therefore the PCs in the LAN do not access.
If someone used Simple Python Server can you suggest me which additional Firewall components I need to modify?
thx
sonia
P.S. I know, I could continue to turn off the Firewall - as I have done up to now - when I make the files available,
but for a cultural reason I would like to know which fact prevents distribution with the Firewall on.