Tf t5 clearer var naming (unpack_inputs decorator tensorflow)
Author: Abdelrhman-Hosny
Pull request: yes

# What does this PR do?

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See #16051 


## Before submitting
- [ ] This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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## Who can review?

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Models:

- albert, bert, xlm: @LysandreJik
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- longformer, reformer, transfoxl, xlnet: @patrickvonplaten
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- gpt2: @patrickvonplaten, @LysandreJik
- rag: @patrickvonplaten, @lhoestq
- tensorflow: @LysandreJik

Library:

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- text generation: @patrickvonplaten
- tokenizers: @n1t0, @LysandreJik
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Documentation: @sgugger

HF projects:

- datasets: [different repo](https://github.com/huggingface/datasets)
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