Could not install stable-diffusion-webui-Layer-Divider in A1111 package getting error C1083: Python.h: No such file or directory

[silverfr0st]

I tried for several days to fix installation of Layer Divider extension (https://github.com/jhj0517/stable-diffusion-webui-Layer-Divider), but it keeps throwing:
fatal error C1083: Python.h: No such file or directory

The problem is not with this particular extension, but with the fact that StabilityMatrix comes with Python on Windows without the folder containing Python.h. And the VS C++ compiler tries to compile additional extensions, but also cannot find Python.h for this. Maybe there is something that can be changed in the Python virtual environment to fix this?

I managed to get around the first error when compiling the pytoshop package, but after that I get another similar error when it tries to compile the pytoshop.packbits extension. I wrote details of the process here - jhj0517/stable-diffusion-webui-Layer-Divider#21 (comment).

How to replicate?
Install latest StabilityMatrix on WIndows 11
Run app and add A1111 package
Run A1111 and install extension from url https://github.com/jhj0517/stable-diffusion-webui-Layer-Divider
Get VS BuildTools from here https://aka.ms/vs/17/release/vs_buildtools.exe and install C++ compiler tools
Restart StabilityMatrix

[silverfr0st]

Fixed with the plugin author.