FastSpeech2 saved_model fails

[sujeendran]

Hi @dathudeptrai,
I am trying to save fastspeech2 same as fastspeech and it always fails.
Here is my code:

And this is the error I'm getting:

I tried passing a concrete function with arguments too. Still can't get it done. I faced similar issue when working on newer versions of tensorflow. But I am using tf2.2 now and I am able to save fs1. Only issue is with FastSpeech2

[dathudeptrai]

@sujeendran fixed, feel free to reopen.