Thanks for all the replies. I',m making screenshots and saving all the good information for reference, thanks
Perhaps for now I will trust that what I installed using apt-get is already verified by apt prior to installation, so no need for to to further verify...
you misunderstood apt doesn't verify the electrum download. You did that using pip.
You installed dependencies via apt and those are verified:
sudo apt-get install python-qt4 python-pip
But the pip install step did not involve apt. You have to verify the electrum tar ball manually
sudo pip install https://download.electrum.org/2.7.18/Electrum-2.7.18.tar.gz