Installation via pip unclear

[BraINstinct0]

• On the official site, it is instructed to use the following command:
  pip3 install jupyterlab_tabnine --user .
• However, over at PyPI, it is as below:
  pip install jupyterlab_tabnine .
• Meanwhile, over at npm, and over here at Github
  (though it's all the way below; would be better to bring it to the top(or at least provide a quick link):
  pip install --upgrade jupyterlab_tabnine

Though there are some peculiar cases that require packages to be installed with a specific flag, I assume these commands essentially are meaning that 'just do the usual pip install'. Is this the case?