T5Tokenizer.from_pretrained("t5-small") returning NoneType
## Environment info
<!-- You can run the command `transformers-cli env` and copy-and-paste its output below.
     Don't forget to fill out the missing fields in that output! -->

- `transformers` version:
- Platform:
- Python version:  Python 3.7.11
- PyTorch version (GPU?):  1.9.0+cu102
- Tensorflow version (GPU?): 2.6.0

-Google colab

### Who can help
@patrickvonplaten, @patil-suraj @sgugger @LysandreJik

Models:

-   t5: @patrickvonplaten, @patil-suraj


Library:


- text generation: @patrickvonplaten
- tokenizers: @LysandreJik


Examples:

- maintained examples (not research project or legacy): @sgugger, @patil-suraj


 -->

## Information

Model I am using (Bert, XLNet ...): t5

The problem arises when using:
* [ ] the official example scripts: (give details below)
tokenizer = T5Tokenizer.from_pretrained("t5-small")




## To reproduce

Steps to reproduce the behavior:
using google colab
1.  tokenizer = T5Tokenizer.from_pretrained("t5-small")  as in
https://huggingface.co/transformers/model_doc/t5.html#transformers.T5Tokenizer
2. type(tokenizer)  -->NoneType 




## Expected behavior
tokenizer should not be NoneType
<!-- A clear and concise description of what you would expect to happen. -->

Hi there, 

PLEASE, do not tag so many people in an issue, usually just tag one or two maintainers. Tagging everyone will unnecessarily disturb. While we  are happy to answer, we would expect people to consider this before opening an issue. Thanks.

Now regarding your issue, did you install `sentencpiece` ? If not the you could
```pip install sentencepiece```
and restart the colab.<|||||>hi Suraj,
       Thanks. It is working.