I’m building a two-unit setup with Raspberry Pi Zero W boards. One Pi acts as the master player; the second Pi will behave purely as a Bluetooth speaker. When a stereo .wav file is uploaded to the master, I need the right channel to play locally through its own audio jack while the left channel streams in real time over Bluetooth to the second Pi. If no Left speaker, then the wav file will play both right and left on the master PI. File transfer to the master should run over Wi-Fi or Bluetooth—whichever proves reliably fast enough—and I’d like the code to allow both paths so I can choose at runtime. On the master Pi I will wire two physical GPIO buttons: one toggles play/pause, the other triggers the file-upload routine. Please deliver well-commented Python (or another lightweight language you prefer on Pi) that: • Receives .wav files wirelessly (supporting both Wi-Fi and Bluetooth transport). • Splits playback so the right channel plays locally and the left channel routes to the paired Pi via Bluetooth (BlueZ/PulseAudio or similar). • Listens for the two hardware buttons and executes the assigned actions instantly. • Provides straightforward setup instructions and any required service or systemd scripts so the whole solution autostarts after reboot. If you can keep dependencies minimal and leverage standard tools like ALSA, bluez, and gpiozero, even better. Once everything boots and the button controls work smoothly with lag-free stereo separation, the job is complete.