Mojave has its own Python installed already. Just run this inside your Terminal :
and you will see that there is a version installed.
So all you had to do to install PIP if you already have installed Python is by typing this:
sudo easy_install pip
and you will have installed PIP after that. I use PIP to Install CodeIntel.
To Install CodeIntel, remember to put Sudo in front of the command.
sudo pip install -U CodeIntel