[Distutils] reproducible builds

[Robin Becker]

An issue has been raised for reportlab to support a specific environment 
variable namely SOURCE_DATE_EPOCH. The intent is that we should get our time 
from this variable rather than time.localtime(time.time()) so that produced 
documents are more invariant.

First off is this a reasonable request? The variable is defined by debian here 
https://reproducible-builds.org/specs/source-date-epoch/

What happens if other distros decide not to use this environment variable? Do I 
really want distro specific code in the package?

In addition we already have our own mechanism for making the produced documents
invariant although it might require an extension to support externally specified 
date & time as in the debian variable.

In short where does the distro responsibility and package maintainers boundary 
need to be?
--
Robin Becker