neural engine for model training?

Can anyone clarify which devices or chips the so-called "neural engine" can be used for machine learning model Training? As opposed to inference (or prediction)? And can external libraries such as Tensorflow (perhaps via the browser-based javascript library) access the neural engine in any manner for training or inference?

From my understanding and information I gathered here and there over time : the neural engine is inferior to the gpu in every aspect for training a TF model and is ... kind of useless to us, developper ? If I extrapolate from the information I found, it's only useful for the tiny model (per today's standard) like the Apple's OCR (eg : you can copy/paste written in image), speech recognition, touchpad gesture, etc ...

neural engine for model training?
 
 
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