Keep Python Open After Running a Script

Question

How do I run a script from the command line but keep the interpreter session open after the script is done?

Answer

Use the -i option at the command line. Thus, if your Python script is foo.py, execute the following at the command line:

python -i foo.py

You'll want to use this feature if you want to inspect or manipulate the variables from the script, or if you've opened a number of windows and don't want them to close when the Python session terminates at the close of the script.