diff --git a/tests/common.mk b/tests/common.mk
index 00cb7261c888f32eccef1e72d235bda309b1817c..39069c4cf23556a3382d2866d3f10bfe7651abe4 100644
--- a/tests/common.mk
+++ b/tests/common.mk
@@ -1,7 +1,7 @@
 #!/usr/bin/make -f
 
 export DEBPYTHON_DEFAULT ?= $(shell sed -rne 's,^default-version = python(.*),\1,p' ../../debian/debian_defaults)
-export DEBPYTHON_SUPPORTED ?= $(shell sed -rne '/^supported-versions/{s/^supported-versions = (.*)/\1/g;s/python//g;s/,//g;p}' ../../debian/debian_defaults)
+export DEBPYTHON_SUPPORTED ?= $(shell sed -rne '/^supported-versions/{s/^supported-versions = (.*)/\1/g;s/python//g}' ../../debian/debian_defaults)
 
 all: run check