diff --git a/docker/accessbot/accessbot.py b/docker/accessbot/accessbot.py
index 39d7134245..0459ccdd30 100755
--- a/docker/accessbot/accessbot.py
+++ b/docker/accessbot/accessbot.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 # Copyright 2011, 2013-2014 OpenStack Foundation
 # Copyright 2012 Hewlett-Packard Development Company, L.P.
diff --git a/docker/accessbot/accessbot.sh b/docker/accessbot/accessbot.sh
index a3c0dee424..f0dbb4bd87 100755
--- a/docker/accessbot/accessbot.sh
+++ b/docker/accessbot/accessbot.sh
@@ -14,4 +14,4 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-exec python /usr/local/bin/accessbot.py -c /etc/accessbot/accessbot.config -l /etc/accessbot/channels.yaml >> /var/log/accessbot/accessbot.log 2>&1
+exec python3 /usr/local/bin/accessbot.py -c /etc/accessbot/accessbot.config -l /etc/accessbot/channels.yaml >> /var/log/accessbot/accessbot.log 2>&1
diff --git a/docker/gitea-init/entrypoint.sh b/docker/gitea-init/entrypoint.sh
index fb927af296..39944e5993 100755
--- a/docker/gitea-init/entrypoint.sh
+++ b/docker/gitea-init/entrypoint.sh
@@ -33,4 +33,4 @@ mkdir -p /data/ssh
 # Template the config file (which can also be root-owned)
 export JINJA_SRC_FILE=/config_src/app.ini.j2
 export JINJA_DEST_FILE=/conf/app.ini
-python /run.py
+python3 /run.py
diff --git a/docker/haproxy-statsd/haproxy-statsd.py b/docker/haproxy-statsd/haproxy-statsd.py
index 7f841e484a..5fe7b52071 100755
--- a/docker/haproxy-statsd/haproxy-statsd.py
+++ b/docker/haproxy-statsd/haproxy-statsd.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 # Copyright (C) 2015 Hewlett-Packard Development Company, L.P.
 #
diff --git a/docker/jinja-init/Dockerfile b/docker/jinja-init/Dockerfile
index 6f4ba22746..0397c7ac3a 100644
--- a/docker/jinja-init/Dockerfile
+++ b/docker/jinja-init/Dockerfile
@@ -31,4 +31,4 @@ RUN pip install jinja2
 
 COPY --from=build /src/jinja-init/run.py /
 
-ENTRYPOINT ["python", "/run.py"]
+ENTRYPOINT ["python3", "/run.py"]
diff --git a/docker/python-builder/scripts/assemble b/docker/python-builder/scripts/assemble
index 7e1ebab8f1..7add890d65 100755
--- a/docker/python-builder/scripts/assemble
+++ b/docker/python-builder/scripts/assemble
@@ -51,7 +51,7 @@ function install_wheels {
     # in the output dir and not the wheel cache, so it's not
     # possible to tell what is the wheel for the project and
     # what is the wheel cache.
-    python setup.py sdist bdist_wheel -d /output/wheels
+    python3 setup.py sdist bdist_wheel -d /output/wheels
 
     # Install everything so that the wheel cache is populated with
     # transitive depends. If a requirements.txt file exists, install
@@ -87,7 +87,7 @@ done
 
 # Use a clean virtualenv for install steps to prevent things from the
 # current environment making us not build a wheel.
-python -m venv /tmp/venv
+python3 -m venv /tmp/venv
 /tmp/venv/bin/pip install -U pip wheel
 
 # If there is an upper-constraints.txt file in the source tree,