app.py

from streamlit_webrtc import webrtc_streamer
webrtc_streamer(key="example",
    # ...
    rtc_configuration={  # Add this config
        "iceServers": [{
        "urls": "turn:a.relay.metered.ca:80",
        "username": "1569e470fe2a2afdb9e2b963",
        "credential": "EG59c3tmBQzU7mMw",
      }]
    }
    # ...
)