The preceding pip install command, whether it is executed explicitly in a virtual environment or at the global level, downloads and installs all of your project dependencies from requirements/_base.txt and requirements/dev.txt. As you can see, you can specify a version of the module that you need for the Django framework and even directly install it from a specific commit at the Git repository, as is done for python-social-auth in our example.

When you have many dependencies in your project, it is good practice to stick to a narrow range of release versions for Python module release versions. Then you can have greater confidence that the project integrity will not be broken because of updates in your dependencies, which might contain conflicts or backward incompatibility. This is particularly important when deploying your project or handing it off to a new developer.

If you have already manually installed the project requirements with pip one by one, you can generate the requirements/_base.txt file using the following command within your virtual environment:

(env)$ pip freeze > requirements/_base.txt