Add dh-python to build dependencies

debian/control

@@ -4,6 +4,7 @@ Priority: standard
 Maintainer: Christoph Biedl <debian.axhn@manchmal.in-ulm.de>
 Build-Depends: debhelper (>= 9.20141010~),
     dh-autoreconf,
+    dh-python,
     python-all,
     python3-all,
     zlib1g-dev,