Python

1. The Isolation property of pip

When installing detectron2 via git+https://github.com/facebookresearch/detectron2.git, you may encounter a ModuleNotFoundError: No module named 'torch' error. This occurs even if torch is already installed. The problem stems from recent versions of pip using isolated builds, which prevent the installation process from accessing installed packages like torch. Using pip install --no-build-isolation 'git+https://github.com/facebookresearch/detectron2.git' can resolve this error.