Time synchronization for bag's topics (Python)

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I have a bag with different topic (RGB, depth, detection and tracking information) that I would like to synchronized (need to know which detection is linked to which frame for example).

My end goal is to apply recognition on each frame in order to add a small ID to the personn detected that will follow him/her on the video.

I found some code in C++ but nothing for Python.

From my understanding I have to create fake subscribers and feed them with the bag's topics in order to use the ApproximateSynchronizer.

Can anyone help me to synchronize topic from bag in Python ? Any help or hint is welcome.