Building local html - no module named pytorch_sphinx_theme

Hi all, I am trying to build local documentation on my Windows system with Anaconda but I am getting an error “No module named pytorch_sphinx_theme” when I try to do so. I have everything from requirements.txt installed and I get this error on my Linux system as well. Here is the traceback:
Traceback (most recent call last):
File “C:\Users\Myles\AppData\Local\Programs\Python\Python311\Lib\site-packages\sphinx\config.py”, line 343, in eval_config_file
exec(code, namespace)
File “C:\Windows\System32\pytorch\docs\source\conf.py”, line 38, in
import pytorch_sphinx_theme
ModuleNotFoundError: No module named ‘pytorch_sphinx_theme’

I’ve tried running “pip install pytorch_sphinx_theme” but that didn’t seem to work. Any advice would be much appreciated! Thanks in advance.

The requirement is specified here and I would assume you could also build it yourself from this repository.