How to get a python script to invoke "python -i" when called normally?

From within script.py, set the PYTHONINSPECT environment variable to any nonempty string. Python will recheck this environment variable at the end of the program and enter interactive mode.

import os# This can be placed at top or bottom of the script, unlike code.interactos.environ['PYTHONINSPECT'] = 'TRUE'  

In addition to all the above answers, you can run the script as simply ./script.py by making the file executable and setting the shebang line, e.g.

#!/usr/bin/python -ithis = "A really boring program"

If you want to use this with the env command in order to get the system default python, then you can try using a shebang like @donkopotamus suggested in the comments

#!/usr/bin/env PYTHONINSPECT=1 python

The success of this may depend on the version of env installed on your platform however.

You could use an instance of code.InteractiveConsole to get this to work:

from code import InteractiveConsolei = 20d = 30InteractiveConsole(locals=locals()).interact()

running this with python script.py will launch an interactive interpreter as the final statement and make the local names defined visible via locals=locals().

>>> i20

Similarly, a convenience function named code.interact can be used:

from code import interacti = 20d = 30interact(local=locals())

This creates the instance for you, with the only caveat that locals is named local instead.

In addition to this, as @Blender stated in the comments, you could also embed the IPython REPL by using:

import IPythonIPython.embed()

which has the added benefit of not requiring the namespace that has been populated in your script to be passed with locals.