Address family not supported by protocol

[crabdancing]

Commands used to build my local copy of the repo:
git clone https://github.com/carlosperate/ardublockly.git
git submodule update --init --recursive
Result is a vague error message. This occurs both with using python2 and python3. Not sure what to do.

uname -a: Linux lithium 4.14.67-1-lts #1 SMP Fri Aug 24 16:54:09 CEST 2018 x86_64 GNU/Linux