No special purpose than to recreate an environment with docopts
The --build-arg is used to pass teh version of docopts to download pre-built binary.
If you're publishing docopts the ../VERSION may not yet reflect a published version.
You can find previously published VERSION in ../tests/VERSION.
docker build -f debian-docopts.Dockerfile --build-arg VERSION=$(cat ./VERSION) -t debian-docopts .
You will have latest python version 0.6.1 in PATH as docopts and Go version in PATH too as docopts0
Golang work space will also be installed if you want to test something.
docker run -it debian-docopts:latest