Installation de l'application VirtualEnv pour votre

pip3 install virtualenv

Collecting virtualenv
  Downloading https://files.pythonhosted.org/packages/f7/69/9a07/virtualenv-16.7.4-py2.py3-none-any.whl (3.3MB)
    100% |████████████████████████████████| 3.3MB 448kB/s
Installing collected packages: virtualenv
Successfully installed virtualenv-20.0.14
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