after pip successful installed: ModuleNotFoundError

Question

I am trying to install the SimPy module so that I can use it in IDLE. However, everytime I try to import in IDLE, I got an error. I already tried reinstalling Python and Pip

Answer 1

I had same problem (on Windows) and the root cause in my case was ANTIVIRUS software! It has "Auto-Containment" feature, that wraps running process with some kind of a virtual machine.
Symptoms are the same: pip install works fine in one cmd line window and import fails when executed from another process.