The superfluous files in /usr/lib/python3/dist-packages/{build,src}/ are generated during dh_auto_test. You may get rid of them with:
diff --git a/debian/rules b/debian/rules index fe0d949..3f4e367 100755 --- a/debian/rules +++ b/debian/rules @@ -4,7 +4,7 @@ export PYBUILD_NAME=ttconv export PYBUILD_BEFORE_TEST=mkdir -p {build_dir}/src; cp -a src/test {build_dir}/src; cp -a debian/> -export PYBUILD_AFTER_TEST=find {build_dir} -name tests.json -type f -delete +export PYBUILD_AFTER_TEST=rm -rf {build_dir}/build {build_dir}/src %: dh $@ --buildsystem=pybuild Cheers, Roderich