Right now dib-python works by trying to find any python on a system in
an order of precedence. A much better way is if we are explicit about
the python we intend to be there which will allow us to make better
decisions in other elements (such as allowing for package-installs to
take into account DIB_PYTHON_VERSION) as well as allow for users to
specify a preferred python version.
Co-Authored-By: Adam Harwell <flux.adam@gmail.com>
Change-Id: Ie609de51cc5fcde701296c9474e315981d9778a2
Creating an element which we can use in #! lines to refer to either
python2 or python3 depending on what it available.
Change-Id: Ic47e18ad21c33ab9f0d11c04260a33725aeee814
