up to 1.4.0; back to python from go
upstream commits:
*
9531a11 - Bye golang! (1 year ago) <Marcin Kulik>
https://github.com/asciinema/asciinema/commit/
9531a11
*
4605040 - Revert "Remove old, python based implementation" (1 year ago) <Marcin Kulik>
https://github.com/asciinema/asciinema/commit/
4605040