diff --git a/containers/docker/Dockerfile b/containers/docker/Dockerfile
index d2c316318ee837b45e7c29751df4f60e6818a4fa..0ce0cef3c01c5ee5f5237cafc12d27e518fddfc2 100644
--- a/containers/docker/Dockerfile
+++ b/containers/docker/Dockerfile
@@ -114,6 +114,7 @@ RUN cd /tmp             \
 
 RUN cd /tmp  \
       && apt-get install -y libtbb-dev \
+      && pip install six \
       && source /usr/local/bin/thisroot.sh \
       && source /usr/local/bin/geant4.sh \
       && source /usr/local/bin/thisdd4hep.sh \