Install and setup of on Raspberry Pi

I have fought the code, and the code won.

I have a Raspberry Pi 3+, am using Python 3.7. I was using wxPython for a simple GUI, but I had to give it up. I cannot get to play a video.

I have tried downloading so many things I’m beginning to worry that some one of them interferes with a legitimate one. For a long time the error message indicated gstream was needed; I finally found an apt-get install command that installed something that eliminated that message, and what I get now is a popup UI dialog saying “Got an invalid playbin (error 2: No such file or directory)”.

Searching for that error message has produced practically nothing, and nothing useful.

I had a deadline and had to switch to another framework to meet it, but I’d like to know how this is supposed to be done in wxPython. I’m not an expert Python programmer, and all the apt and apt-get things look to me like a bunch of trial-and-error a lot of the time. The wxPython site indicates that is an optional package, so it isn’t included in a normal Python 3 installation on all platforms.

That’s fine, but is there, anywhere, a list of steps to go from some known state – right after a Python 3 install on a Pi, perhaps – to a set of wxPython and other libraries that will support wx.mediaCtrl? And maybe even an example or two that would run on a Pi after I followed those steps?