Wav2Vec2ForCTC is not BaseModelOutput
On the website of huggingface: https://huggingface.co/transformers/model_doc/wav2vec2.html#wav2vec2forctc
it says Wav2VecForCTC is "BaseModelOutput".
But actually it is "CausalLMOutput", it has no attribute 'last_hidden_state' or the others of "BaseModelOutput".
Its returns should belong to "CausalLMOutput": https://huggingface.co/transformers/main_classes/output.html#causallmoutput

**The description of the returns of Wav2VecForCTC on the website:**
<img width="1031" alt="130951325-9fd86ab4-4b2a-4965-b4bf-88b2cc556b46" src="https://user-images.githubusercontent.com/15671418/131300701-11106f9c-ab2a-42b8-8c35-9a7418e37474.png">

**The error when call "the last hidden state" of Wav2VecForCTC:**
<img width="663" alt="130951343-eb4655a3-af57-4a2f-a387-0fa628f854dc" src="https://user-images.githubusercontent.com/15671418/131300840-107609a5-6d30-4d89-a0e1-ae003feb3934.png">

**The description of CasualLMOutput which the Wav2VecForCTC shoud be:**
<img width="1077" alt="130951334-093e1df0-6207-45f0-b803-76b276f17f7b" src="https://user-images.githubusercontent.com/15671418/131300953-a8eaf063-db8d-46f3-836e-4baf534e1554.png">

@patrickvonplaten
Hi @patrickvonplaten , I read the source code and found the wav2vecctc only conducts word-level tokenization. Does it  support ctc fine-tuning on grapheme level or character level? Thanks.<|||||>Oh yeah that's a typo in the docs indeed, but it's already fixed on master I think :-) 
See: https://huggingface.co/transformers/master/model_doc/wav2vec2.html#wav2vec2forctc<|||||>This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

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