AttributeError: 'NoneType' object has no attribute 'prop'

I’ve got a python-based snap (pydoro) and I’m so close to getting it fully working.

I’ve run into an issue getting it to play it’s timer wav file:

AttributeError: 'NoneType' object has no attribute 'prop'

The internet says I need gstreamer1.0-gtk3 - that didn’t work. You’ll see that I nearly mirrored the build/stage-packages to see if the application was looking for these packages during the build stage.

Here’s my snapcraft.yaml:

name: pydoro
adopt-info: pydoro
summary: Terminal Pomodoro Timer
description: |
  Terminal Pomodoro Timer

license: MIT

base: core20
grade: stable
confinement: strict
compression: lzo

assumes:
  - command-chain
  
apps:
  pydoro:
    command: bin/pydoro
    command-chain: 
      - bin/homeishome-launch      
    environment:
      LC_ALL: C.UTF-8
      PYTHONPATH: $SNAP/usr/lib/python3/dist-packages
      GI_TYPELIB_PATH: $SNAP/usr/lib/$SNAPCRAFT_ARCH_TRIPLET/girepository-1.0
    plugs:
      - home
      - audio-playback
      
parts:
  pydoro:
    source: https://github.com/JaDogg/pydoro
    source-type: git
    plugin: python
    
    override-pull: |
      snapcraftctl pull
      snapcraftctl set-version "$(git describe --tags | sed 's/^v//' | cut -d "-" -f1)"

    build-packages:
      - python3
      - python3-gi
      - python3-pip
      - python3-pygame
      - python3-gst-1.0      
      
    stage-packages:
      - python3
      - python3-gi
      - python3-pygame
      - python3-gst-1.0
      - gstreamer1.0-libav
                        
  homeishome-launch:
    plugin: nil
    stage-snaps:
      - homeishome-launch  

Does anyone have any ideas?

Okay I got one error fixed, now a new one!

same as this post: Pygame.error: Mixer not initialized