The test suite passes on Python 2.7, but reports multiple failures on Python 3.4 and later.
The Python 3 standard library configparser.BasicInterpolation behaviour now calls the parser's get method, as of https://hg.python.org/cpython/rev/267422f7c927
configparser.BasicInterpolation
get
This change causes interpolation to fail with the SchemaConfigParser class.
SchemaConfigParser
As an interim measure, we should at least remove Python 3.4 and 3.5 from the trove classifiers for the distribution.
The changes in the Python 3 standard library were introduced to resolve https://bugs.python.org/issue21159 and there is some discussion of the problems this caused for dependent distributions.
The problems for this code base are discussed in an earlier report for Configglue, at https://bugs.launchpad.net/configglue/+bug/1504288