## 2.2 Splitting the job up

Running `setup.py install` builds and installs all modules in one fell swoop. If you prefer to work incrementally--especially useful if you want to customize the build process, or if things are going wrong--you can use the setup script to do one thing at a time. This is particularly helpful when the build and install will be done by different users--e.g., you might want to build a module distribution and hand it off to a system administrator for installation (or do it yourself, with super-user privileges).

For example, you can build everything in one step, and then install everything in a second step, by invoking the setup script twice:

      python setup.py build
      python setup.py install

(If you do this, you will notice that running the `install` command first runs the `build` command, which quickly notices that it has nothing to do, since everything in the build directory is up-to-date.)

** concrete reason for splitting things up? **