STOP!
This folder contains the legacy Keras code which is stale and about to be deleted. The current Keras code lives in github/keras-team/keras.
Please do not use the code from this folder.
The fact they didn't find the same mistake(s) in keras-team/keras (I assume they scanned, it's one of the most popular Python repo) makes me believe these issues have been fixed/removed in up-to-date karas repo.