Openai gpt for classification
Author: fmcurti
Pull request: yes
Labels: name: model card

# What does this PR do?
Adds  sequence classification architecture for GPT-1,
Strongly based on modifications made in #7501

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Fixes #7623 (issue) (Partially)


## Before submitting
- [ ] This PR fixes a typo or improves the docs (you can dimiss the other checks if that's the case).
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- [✓] Did you write any new necessary tests? 


## Who can review?

Anyone in the community is free to review the PR once the tests have passed. Feel free to tag
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 albert, bert, GPT2, XLM: @LysandreJik 
 tokenizers: @mfuntowicz
 Trainer: @sgugger
 Speed and Memory Benchmarks: @patrickvonplaten
 Model Cards: @julien-c
 Translation: @sshleifer
 Summarization: @sshleifer
 TextGeneration: @TevenLeScao 
 examples/distillation: @VictorSanh
 nlp datasets: [different repo](https://github.com/huggingface/nlp)
 rust tokenizers: [different repo](https://github.com/huggingface/tokenizers)
 Text Generation: @TevenLeScao
 Blenderbot, Bart, Marian, Pegasus: @sshleifer
 T5: @patrickvonplaten
 Longformer/Reformer: @patrickvonplaten
 TransfoXL/XLNet: @TevenLeScao 
 examples/seq2seq: @sshleifer
 examples/bert-loses-patience: @JetRunner
 tensorflow: @jplu
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Comments:
Hello! Thanks a lot for opening this PR. It seems that in the process, you ran a merge that went somewhat unexpectedly, as there's now 37 files changes and a +1960/-40 diff, which makes it impossible to review. Do you mind opening a new PR with only your commits, so that we can review it?

> Hello! Thanks a lot for opening this PR. It seems that in the process, you ran a merge that went somewhat unexpectedly, as there's now 37 files changes and a +1960/-40 diff, which makes it impossible to review. Do you mind opening a new PR with only your commits, so that we can review it?

Yes of course, I'll close this one and open a new PR