diff --git a/tests/functional/qemu_test/asset.py b/tests/functional/qemu_test/asset.py
index 559af0351f..c5d3e73c4b 100644
--- a/tests/functional/qemu_test/asset.py
+++ b/tests/functional/qemu_test/asset.py
@@ -39,6 +39,9 @@ class Asset:
         return "Asset: url=%s hash=%s cache=%s" % (
             self.url, self.hash, self.cache_file)
 
+    def __str__(self):
+        return str(self.cache_file)
+
     def _check(self, cache_file):
         if self.hash is None:
             return True