bug#65127: Python-pytorch slow

[Cayetano Santos]

Hi guix,

  I just noticed that the following line (latest guix, as for today)

    guix shell -C --emulate-fhs --network python python-pytorch 
python-torchvision -- python3 quickstart_tutorial.py

  with

    
https://raw.githubusercontent.com/pytorch/tutorials/main/beginner_source/basics/quickstart_tutorial.py

  is noticeably slower than the version of the torch suite provided by
  conda, for example.

Thanks,

Cayetano Santos