OS: gLinux Rodete

Running lab_tools/setup_lab_tools, per sites/chromeos/for-team-members/infrastructure/lab-tools, fails when it reaches a point which requires Matplotlib, with the message:

ERROR| Unable to build and install Matplotlib.                             
Error: None

The problem has been isolated to build_externals.py (cs/chromeos_public/src/third_party/autotest/files/utils/build_externals.py?l=154), but the fix fora similar in the past relied on lab_tools/finish_update.py to install python-matplotlib before build_externals was run.