python-language-server[all] not working if installing with pip3

ice-python doesn't work when installing with the code `python3 -m pip install python-language-server[all]`. It does with `python -m pip install python-language-server[all]`. I have faced this problem in other packages, could someone explain me why does this happen?

As I have understood, pip is not going to be supported. So I'd rather prefer to install everything with pip3, instead of pip. Although, when I install a package with pip it's also available for python3 kernel.

I wouldn't like to have many duplicates, that's why I try to install all the packages with pip3. If you install with pip is the same than pip3? Problems like the one described above make me nuts to install packages with pip instead pip3.

Commencez par reproduire l’installation avec `python3 -m pip install python-language-server[all]` et comparez-la avec `python -m pip install python-language-server[all]`, notamment en vérifiant quels environnements Python et kernel sont utilisés. La tâche sera considérée comme terminée lorsqu’il aura été déterminé si le problème concerne ce projet et que le comportement de l’installation ainsi que la commande pip prise en charge auront été documentés ou corrigés.

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