This bug is only present on old release still available through pypi, so installing the library using pip, because a quite old version is distributed:
Name: secureconfig
Version: 0.1.1.0
Summary: Configuration-oriented encryption toolkit to make secure config files simple
Home-page: https://bitbucket.org/nthmost/python-secureconfig
Author: Naomi Most
Author-email: naomi@nthmost.net
I insert a comment here about it.
It would be sufficient insert the highlighted commit diff in the pypi release to fix this issue.
Best regards