Been looking around, but can't find a hard and fast answer: how large exactly is an install of python, straight from here: https://www.python.org/downloads/
Edit: currently doing it on a unix system
232 megabytes for 3.6.1 (this is a local version that is fully functional) on ubuntu 14.04 and created canonically using
.configure
make
make install
etc.
(i.e. the instructions from the python docs)