pip install requirements.txt package from source no github

Question

I'm trying to write a requirements.txt that includes this:

pip3 install torch==1.9.0+cu111 torchvision==0.10.0+cu111 torchaudio==0.9.0 -f https://download.pytorch.org/whl/torch_stable.html

already tryied to include in requirements.txt:

torch==1.9.0+cu111 -f https://download.pytorch.org/whl/torch_stable.html

or

torch==1.9.0+cu111 @ https://download.pytorch.org/whl/torch_stable.html

but doesn't work.

It's always an option to do it manually but will be great if can be included in the requirements.txt file.

I'll appreciate your help, thanks.

PD: When downloading, sometimes there is a connection error with the pytorch server, I realized is normal, just have to try multiple times.