TFAlbertMainLayer cannot be imported from the transformers library.
Unlike the TFBertMainLayer class which can be imported from transformers, TFAlbertMainLayer cannot be imported.

Locally I made the changes to init.py:

Import TFAlbertMainLayer from modeling_tf_albert 

Similar to tensorflow version, pytorch version should also be implemented.
This seems like a valid point, what do you think @LysandreJik?