This old version is still using python.eclass. Opening a tracking bug since it has revdeps.
Closing, as it is no longer the case for the remaining ebuilds. $ grep -R inherit graphviz-2.40.1.ebuild:inherit autotools eutils flag-o-matic java-pkg-opt-2 multilib python-single-r1 qmake-utils graphviz-2.38.0-r1.ebuild:inherit autotools eutils flag-o-matic java-pkg-opt-2 multilib python-single-r1 qmake-utils