This is useful on systems like NixOS, where python3 is not in
/usr/bin/python3 as well as for people using alternative ways to
install python such as virtualenv/pyenv.
This is useful to check that compression actually works, and how
compression influences file size in the best-case-scenario for
compression. (The answer is that not as much as one would hope:
there's still a big overhead of the indexing and since every field
is compressed separately, even fields that compress very well
contribute to the file size. This overhead becomes negligible only
for very big fields.)
