The misconfiguration is triggered by Build-Depends: python3-all, python3-setuptools
When I remove this reference to python3 then build proceeds normally under python2. That's good enough as a work around. But the bug still remains, that python3 is used (if the python3-all Build-Depends is present) even if dh --with python3 is not specified. Regardless of the Build-Depends settings, the dh configuration is ignored. Drew
