From f26e390a40288be2801b3b9b3a99269b3f3ff81f Mon Sep 17 00:00:00 2001
From: Andrew Morgan <1342360+anoadragon453@users.noreply.github.com>
Date: Tue, 1 Mar 2022 13:55:18 +0000
Subject: [PATCH] Use Python 3.9 in Synapse dockerfiles by default (#12112)

---
 changelog.d/12112.docker | 1 +
 docker/Dockerfile        | 4 ++--
 2 files changed, 3 insertions(+), 2 deletions(-)
 create mode 100644 changelog.d/12112.docker

diff --git a/changelog.d/12112.docker b/changelog.d/12112.docker
new file mode 100644
index 000000000..b9e630653
--- /dev/null
+++ b/changelog.d/12112.docker
@@ -0,0 +1 @@
+Use Python 3.9 in Docker images by default.
\ No newline at end of file
diff --git a/docker/Dockerfile b/docker/Dockerfile
index e4c1c19b8..a8bb9b0e7 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -11,10 +11,10 @@
 # There is an optional PYTHON_VERSION build argument which sets the
 # version of python to build against: for example:
 #
-#    DOCKER_BUILDKIT=1 docker build -f docker/Dockerfile --build-arg PYTHON_VERSION=3.9 .
+#    DOCKER_BUILDKIT=1 docker build -f docker/Dockerfile --build-arg PYTHON_VERSION=3.10 .
 #
 
-ARG PYTHON_VERSION=3.8
+ARG PYTHON_VERSION=3.9
 
 ###
 ### Stage 0: builder