Susnato Dhar

Results 3 issues of Susnato Dhar

I tried to convert it to Tensorflow 2.x backend compatible. Requirements: Tensorflow 2.X =>Tested on Tensorflow==2.6.0

# What does this PR do? Adds Pop2Piano model to HuggingFace. Fixes #20126 ## Before submitting - [ ] This PR fixes a typo or improves the docs (you can...

Adds XLNET Tokenizer to the library. The part 2 of adding the `xlnet` to keras-nlp.