Tokenizer problem for model 'patrickvonplaten/longformer-random-tiny'
Author: lessenko
Pull request: no

## Environment info
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- `transformers` version: 3.4.0
- Platform: Ubuntu 18.04.5 LTS
- Python version: Python 3.6.9
- PyTorch version (GPU?):1.6.0
- Tensorflow version (GPU?):2.3.1
- Using GPU in script?:No
- Using distributed or parallel set-up in script?:No

### Who can help
T5: @patrickvonplaten
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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: @patrickvonplaten @TevenLeScao
 blenderbot: @mariamabarham
 Bart: @sshleifer
 Marian: @sshleifer
 T5: @patrickvonplaten
 Longformer/Reformer: @patrickvonplaten
 TransfoXL/XLNet: @TevenLeScao
 RAG: @patrickvonplaten, @lhoestq
 FSTM: @stas00
 examples/seq2seq: @sshleifer
 examples/bert-loses-patience: @JetRunner
 tensorflow: @jplu
 examples/token-classification: @stefan-it
 documentation: @sgugger
 -->

## Information

Model I am using (patrickvonplaten/longformer-random-tiny):

The problem arises when using:
* [ ] the official example scripts: (give details below)
https://huggingface.co/patrickvonplaten/longformer-random-tiny

## To reproduce

Steps to reproduce the behavior:

1. Running the script.
2. Result:
_2020-11-08 11:09:14.631646: W tensorflow/stream_executor/platform/default/dso_loader.cc:59] Could not load dynamic library 'libcudart.so.10.1'; dlerror: libcudart.so.10.1: cannot open shared object file: No such file or directory
2020-11-08 11:09:14.631672: I tensorflow/stream_executor/cuda/cudart_stub.cc:29] Ignore above cudart dlerror if you do not have a GPU set up on your machine.
Traceback (most recent call last):
  File "test_tiny.py", line 3, in <module>
    tokenizer = AutoTokenizer.from_pretrained("patrickvonplaten/longformer-random-tiny")
  File "/usr/local/lib/python3.6/dist-packages/transformers/tokenization_auto.py", line 333, in from_pretrained
    return tokenizer_class_py.from_pretrained(pretrained_model_name_or_path, *inputs, **kwargs)
  File "/usr/local/lib/python3.6/dist-packages/transformers/tokenization_utils_base.py", line 1591, in from_pretrained
    list(cls.vocab_files_names.values()),
OSError: Model name 'patrickvonplaten/longformer-random-tiny' was not found in tokenizers model name list (allenai/longformer-base-4096, allenai/longformer-large-4096, allenai/longformer-large-4096-finetuned-triviaqa, allenai/longformer-base-4096-extra.pos.embd.only, allenai/longformer-large-4096-extra.pos.embd.only). We assumed 'patrickvonplaten/longformer-random-tiny' was a path, a model identifier, or url to a directory containing vocabulary files named ['vocab.json', 'merges.txt'] but couldn't find such vocabulary files at this path or url.
_
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## Expected behavior

I suppose two files are needed - 'vocab.json', 'merges.txt'.
Thanks.

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Comments:
Hey @lessenko - the model is useless for any real application as it's just randomly initialized. It's only used for testing purposes.

Hi  @patrickvonplaten,
Thanks.