def METHOD_NAME(self) -> dict[str, dict]:
    """Calculate the storage usage of each camera."""
    usages: dict[str, dict] = {}
    for camera in self.config.cameras.keys():
        camera_storage = (
            Recordings.select(fn.SUM(Recordings.segment_size))
            .where(Recordings.camera == camera, Recordings.segment_size != 0)
            .scalar()
        )
        usages[camera] = {
            "usage": camera_storage,
            "bandwidth": self.camera_storage_stats.get(camera, {}).get(
                "bandwidth", 0
            ),
        }
    return usages