When I installed Python, I installed 2.7 and 3.4. I am using XP. I have been using Python 3 by just right clicking on a py file and choose Edit with Idle. That works just fine when I am using 3, but since I also use 2.7 for practice from online courses I haven't figured out how to use the interactive shell.
What I do when I need to run 2.7 code is to just save the file to my Python 2.7 folder and run a command prompt. I then just type the py file. That works but I am left with a dos prompt when the file finishes. I sometimes would like to be able to use the interactive shell with a 2.7 file in memory. I don't know how to do that. -- https://mail.python.org/mailman/listinfo/python-list