This worked for me, thanks!

Thanks, this worked for me. I also needed to upgrade pip: /Library/Frameworks/Python.framework/Versions/3.7/bin/python3.7 -m pip install --upgrade pip …and install numpy: sudo pip3 install numpy

This worked for me, thanks. For posterity, Install Certificates.command is located at /Applications/Python 3.7 after the installer completes. I also had to upgrade pip /Library/Frameworks/Python.framework/Versions/3.7/bin/python3.7 -m pip install --upgrade pip, and install numpy sudo pip3 install numpy.