How to do it...

1. Environment variables are accessed via Python's os.environ.
2. Because the environ object is a dictionary, you can specify a particular variable to view:

      >>> import os
      >>> print(os.environ["PATH"])
      /home/cody/anaconda3/bin:/home/cody/bin:/home/cody/
      .local/bin:/usr/local/sbin:/usr/local/bin:/usr
       /sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games 

1. Adding a new variable is as simple as follows:

      >>> os.environ["PYTHONOPTIMIZE"] = "1"