Cannot Stream From WAN remote Rpi using Python Server and Client Sockets

Question

This is the first time I've ever asked a question to any on-line group, so apologies if this is the wrong place to ask this. I am trying to use stream live video using Python Server and Client sockets from my WAN remote RPi's camera module. To test it, I have put the client script on the RPi, with the server script on my home computer and run them both locally on my LAN connection on my local router, and I can successfully see the LAN streamed image over Python. This tells me the camera works, the RPi works, and the server and clients scripts both work using a 192.168 IP address. However, when I swap the LAN IP address for my WAN IP address number on both scripts, I get a "Win Error 10049, the requested address is not valid in this context". If I'm not supposed to use the WAN IP from my local computer to make the connection - what IP address should I use? I've tried using the remote RPi's WAN address and that didn't work either. I hope someone can say what I'm doing wrong. Many thanks, John