Issue: Import Error in Kaggle notebook

Comment:
@lhoestq I did, and then let pip handle the installation in `pip import datasets`. I also tried using conda but it gives the same error.

Edit: pyarrow version on kaggle is 4.0.0, it gets replaced with 4.0.1. So, I don't think uninstalling will change anything.
```
Install Trace of datasets:

Collecting datasets
  Downloading datasets-1.9.0-py3-none-any.whl (262 kB)
     |████████████████████████████████| 262 kB 834 kB/s eta 0:00:01
Requirement already satisfied: dill in /opt/conda/lib/python3.7/site-packages (from datasets) (0.3.4)
Collecting pyarrow!=4.0.0,>=1.0.0
  Downloading pyarrow-4.0.1-cp37-cp37m-manylinux2014_x86_64.whl (21.8 MB)
     |████████████████████████████████| 21.8 MB 6.2 MB/s eta 0:00:01
Requirement already satisfied: importlib-metadata in /opt/conda/lib/python3.7/site-packages (from datasets) (3.4.0)
Requirement already satisfied: huggingface-hub<0.1.0 in /opt/conda/lib/python3.7/site-packages (from datasets) (0.0.8)
Requirement already satisfied: pandas in /opt/conda/lib/python3.7/site-packages (from datasets) (1.2.4)
Requirement already satisfied: requests>=2.19.0 in /opt/conda/lib/python3.7/site-packages (from datasets) (2.25.1)
Requirement already satisfied: fsspec>=2021.05.0 in /opt/conda/lib/python3.7/site-packages (from datasets) (2021.6.1)
Requirement already satisfied: multiprocess in /opt/conda/lib/python3.7/site-packages (from datasets) (0.70.12.2)
Requirement already satisfied: packaging in /opt/conda/lib/python3.7/site-packages (from datasets) (20.9)
Collecting xxhash
  Downloading xxhash-2.0.2-cp37-cp37m-manylinux2010_x86_64.whl (243 kB)
     |████████████████████████████████| 243 kB 23.7 MB/s eta 0:00:01
Requirement already satisfied: numpy>=1.17 in /opt/conda/lib/python3.7/site-packages (from datasets) (1.19.5)
Requirement already satisfied: tqdm>=4.27 in /opt/conda/lib/python3.7/site-packages (from datasets) (4.61.1)
Requirement already satisfied: filelock in /opt/conda/lib/python3.7/site-packages (from huggingface-hub<0.1.0->datasets) (3.0.12)
Requirement already satisfied: urllib3<1.27,>=1.21.1 in /opt/conda/lib/python3.7/site-packages (from requests>=2.19.0->datasets) (1.26.5)
Requirement already satisfied: idna<3,>=2.5 in /opt/conda/lib/python3.7/site-packages (from requests>=2.19.0->datasets) (2.10)
Requirement already satisfied: certifi>=2017.4.17 in /opt/conda/lib/python3.7/site-packages (from requests>=2.19.0->datasets) (2021.5.30)
Requirement already satisfied: chardet<5,>=3.0.2 in /opt/conda/lib/python3.7/site-packages (from requests>=2.19.0->datasets) (4.0.0)
Requirement already satisfied: typing-extensions>=3.6.4 in /opt/conda/lib/python3.7/site-packages (from importlib-metadata->datasets) (3.7.4.3)
Requirement already satisfied: zipp>=0.5 in /opt/conda/lib/python3.7/site-packages (from importlib-metadata->datasets) (3.4.1)
Requirement already satisfied: pyparsing>=2.0.2 in /opt/conda/lib/python3.7/site-packages (from packaging->datasets) (2.4.7)
Requirement already satisfied: python-dateutil>=2.7.3 in /opt/conda/lib/python3.7/site-packages (from pandas->datasets) (2.8.1)
Requirement already satisfied: pytz>=2017.3 in /opt/conda/lib/python3.7/site-packages (from pandas->datasets) (2021.1)
Requirement already satisfied: six>=1.5 in /opt/conda/lib/python3.7/site-packages (from python-dateutil>=2.7.3->pandas->datasets) (1.15.0)
Installing collected packages: xxhash, pyarrow, datasets
  Attempting uninstall: pyarrow
    Found existing installation: pyarrow 4.0.0
    Uninstalling pyarrow-4.0.0:
      Successfully uninstalled pyarrow-4.0.0
Successfully installed datasets-1.9.0 pyarrow-4.0.1 xxhash-2.0.2
WARNING: Running pip as root will break packages and permissions. You should install packages reliably by using venv: https://pip.pypa.io/warnings/venv
```