WARNING: You are using pip version 19.2.3, however version 20.2 is available. You should consider upgrading via the ‘python -m pip install –upgrade pip’ command.

// full error message
WARNING: You are using pip version 19.2.3, however version 20.2 is available.
You should consider upgrading via the 'python -m pip install --upgrade pip' command.

// run
python -m pip install --upgrade pip --user --trusted-host files.pythonhosted.org --trusted-host pypi.org