class SourceMedia():
    """Source media used by eg feature extractors. This is a list of Source objects.

    JSON type schema:
    [{
        "source": "/path/to/video.mp4",
        "path": "/path/to/video.mp4",
        "provider": "FileInputJSON"
    },
    {
        "source": "http://example.com/video.mp4",
        "path": "/path/to/downloaded_video.mp4",
        "provider": "InputYAML"
    }]

    It should be possible to combine/merge/aggregate multiple SourceMedia into one