Extract a a method to encapsulate behavior and documentation. Rewrite for loop as legacy-style dictionary comprehension.

Fix "dictionary changed size during iteration"

env is being modified at the same time as being iterated which leads to RuntimeError: dictionary changed size during iteration.

Dropping support for Python 3.2 and earlier Python 3 versions. Currently only log a warning, but future versions will fail.

Another refactor of findall, this time separating the simple walk / join operation from the conditional relative path.

Add tests capturing expected behavior, including failure to match expectation indicated in docstring.