diff --git a/tests/sched_change_priority/tests/01-run.py b/tests/sched_change_priority/tests/01-run.py
index 37a313dd1d7eb..c6ebaf4aee350 100755
--- a/tests/sched_change_priority/tests/01-run.py
+++ b/tests/sched_change_priority/tests/01-run.py
@@ -9,7 +9,7 @@ def testfunc(child):
     child.expect(r"Run \"nice (\d+) (\d+)\"\r\n")
     pid = int(child.match.group(1))
     prio = int(child.match.group(2))
-    child.sendline(f"nice {pid} {prio}")
+    child.sendline("nice {} {}".format(pid, prio))
     child.expect_exact('[t3] Running again.')