Implement tool for saved Keras model files inspection, diff and patching

[pmasousa]

It consists of three sub features, that allow:
Visualization of the contents of .keras and .weights.h5 files in a notebook, where you can further expand the contents up until the weights of the file. Diff of a model compared to a reference model, being presented side by side with the differences highlighted. Patching a model, where it is possible to change a layer's name and changing a specified weight of a model.

Please let us know if this is what you had in mind.

closes #19705

[fchollet]

Thanks for the PR! Do you have a Colab notebook that demos the new features?

[pmasousa]

Yes, here

I couldn't implement the changes in the saved weights file, only in a .keras file.
If you could explain how to do it I would appreciate it.

[fchollet]

Great work! Here are some things we should do.

1. For every display output, there should be a shell mode (plain text with text color tags) and a notebook mode (html). We route to one or the other based on whether we detect we are in a notebook or not.
2. The diff isn't super useful. What we should do is:
   • Compare the model structure; for instance if a layer is absent from one model but present in the other, we should highlight that. We should display the names of those layers, and the count of weights and sublayers associated with it.
   • For each layer that matches (by path) across the models, we should compare the weight structure (number of weights, weights shapes, dtypes) and highlight any differences.
3. The edit tool can be a class, e.g.

editor = KerasFileEditor(filepath)
editor.list_layer_paths()  # Return all layer paths
editor.layer_info(layer_path)  # Show weight structure for this layer
editor.edit_layer(layer_path, new_name=..., new_vars=...)
editor.write_out(filepath)

I couldn't implement the changes in the saved weights file, only in a .keras file.

They aren't very different -- the weights file is one of the files present in the .keras file. You only need to implement these features for the weights file, then the same code will also work for the .keras file.

[pedro-curto]

Thank you very much for your feedback, we really appreciate it!

We're currently on our degree's final two weeks, so everything is very intensive right now and we barely have any time because of the projects. We would really like to make those changes and get back to you because we enjoyed working on this feature and would like it to be as good as possible and according to your needs and the specification. We will get back to you and make the required changes starting next week, if that is ok with you. Again, thanks for your time, patience and feedback!

[fchollet]

Sure -- there's no rush! Thanks for working on this!

[pedro-curto]

Hello. Sorry for taking so long.
We've made a commit with the changes that we believe that match your feedback on the things we should do on the tool. We have a link to a colab that we prepared, in case you want to test the functionalities and see what we changed and how in an interactive way: it's this colab. Is this what you had in mind?
Any feedback is greatly appreciated, and thank you for your time and patience with us so far!