Create model_cards for Chinese Couplet and Poem GPT2 models  
Author: hhou435
Pull request: yes
Labels: name: model card

# What does this PR do?

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 albert, bert, XLM: @LysandreJik
 GPT2: @LysandreJik, @patrickvonplaten
 tokenizers: @mfuntowicz
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 Benchmarks: @patrickvonplaten
 Model Cards: @julien-c
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 nlp datasets: [different repo](https://github.com/huggingface/nlp)
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Comments:
Really cool, and great that you inputed custom widget inputs. Merging.

cc'ing @JetRunner for info