
install_requires: In order to build PyTorch, we need pyyaml. Setuptools will handle making sure that pyyaml will be available, downloading and installing it if necessary

We will consider these components in more detail, but for now it is instructive to look at the end product of an installation -- i.e. what Setuptools does after building the code.
site_packages
Third party packages are by default installed into the lib/<version>/site_packages  directory associated with your Python binary. For example, because I am using an Miniconda environment, my Python binary is found at:
(p3) killeent@devgpu047:pytorch (master)$ which python
~/local/miniconda2/envs/p3/bin/python

And thus packages are installed into:
/home/killeent/local/miniconda2/envs/p3/lib/python3.6/site-packages

I installed PyTorch, and let's take a look into torch folder in site-packages:
```bash
(p3) killeent@devgpu047:site-packages$ cd torch