ID 555716 - [CopyCat][DistTraining] Windows cannot use IPv4 to train

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Problem summary
When trying to train CopyCat Distributed training with an IPv4 address as the main address on Windows it fails to establish a connection and train.

Customer reported version
Nuke 15.0v1

Customer reported platform
Windows 10  

Steps to reproduce
1) Go to Command Prompt and run in this command: ipconfig

2) Copy the IPv4 from your Windows properties.

3) set up distributed training with a command line that looks like the following, and press Enter:
set COPYCAT_MAIN_ADDR=IPv4Addr 
set COPYCAT_MAIN_PORT=30000
set COPYCAT_RANK=0 
set COPYCAT_WORLD_SIZE=2
./Nuke14.1v1/Nuke14.1 --nukex -i -F 1 -X CopyCat1 --gpu /path/to/attached/script.nk

Expected behaviour
It says that it is waiting to start with a rank of 0

Actual behaviour
CopyCat doesn't train and instead complains about the address [W socket.cpp:558] [c10d] The IPv4 network addresses of (IPv4 adress, 30000) cannot be retrieved (gai error: -9 - Address family for hostname not supported)

Workaround
Use the IPv6 address, rather than IPv4 address.

Reproduced by support
This bug has been reproduced in:
Nuke 15.0v1 - Windows 
Nuke 14.1v1 - Windows 

Earliest version tested
Nuke 14.1v1 
- This feature did not exist before this version

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