diff --git a/common_py/Dockerfile b/common_py/Dockerfile
index e05997237c40a4a305cc8ecddc421e634a78c3ba..265644cd9adbaec2b716f30d6841496bd06f8007 100755
--- a/common_py/Dockerfile
+++ b/common_py/Dockerfile
@@ -4,7 +4,8 @@ FROM python:3.13-slim AS base
 ARG PIP_CACHE_DIR=
 ARG APT_CACHE_DIR=
 RUN rm -f /etc/apt/apt.conf.d/docker-clean
-RUN if ! [ -z "$APT_CACHE_DIR" ]; then echo "Dir::Cache::Archives $APT_CACHE_DIR" > /etc/apt/apt.conf.d/ci_caching; fi
+RUN if ! [ -z "$APT_CACHE_DIR" ]; then echo "Dir::Cache::Archives '$APT_CACHE_DIR'" > /etc/apt/apt.conf.d/ci_caching; fi
+RUN cat /etc/apt/apt.conf.d/ci_caching
 
 WORKDIR /code