I'm going to tackle the questions one-by-one: 

I would like these ".py" files to be IDLE files in the sense that they have the IDLE icon and they open up directly into an idle file with a shell in the background. For context: on my other Windows 10 machine, I've been able to amass a semester's worth of ".py" that are all opened by, and have the icon of, IDLE. 

I have tried to manually associate the ".py" in the "default programs" app with the IDLE application shortcut but to no avail. Instead of opening in IDLE it opens in the command line format (that black python icon). So basically it opens up for a fraction of a second and then closes. No bueno. 

I have tried repairing, installing and reinstalling Python on my machine all with the appropriate settings (and launcher included in all of those tries). No dice. Still no right-click context menu. Still no ability to have ".py" files open up with IDLE. 

Note: I _have_ been able to associate the ".py" extension with "idle.bat" -- this works. But that's not an acceptable workaround. There is something deeper wrong here that I cannot pinpoint. Is it in my installer? I have no idea. I've tried most everything...

Including deleting the UserChoice key/folder/whatever it is and still nothing producing. I even tried "idle.exe" but Windows 10 gives me the error: "This app can't run on your PC -- to find a version for your PC, contact the software publisher." Just great. 

There are no error messages on any install/reinstall/repair that I've managed to try. Everything goes smoothly from start to finish. But the product is broken. 

In addition: I've never programmed in 2.7 and have never installed it on my computer. All of my Python knowledge is based in 3.5.2: it was for a semester-long course. So even the repair that I did run (which didn't work) wouldn't be accounting for any potential conflicts with 2.7. 

Furthermore, I was not able to find a python rocket icon in my files even with hidden items in view so I was not able to complete the ".py" and ".pythonrocketapp" association. However, I did notice in my program/applications folder that Python Launcher was indeed installed on my computer at the very least. 

This is absolutely perplexing and I appreciate all of your help in troubleshooting this. Thank you, and Merry Christmas.