diff --git a/tests/test_manifest_xml.py b/tests/test_manifest_xml.py
index bfdf366..6095c72 100644
--- a/tests/test_manifest_xml.py
+++ b/tests/test_manifest_xml.py
@@ -579,4 +579,6 @@
     self.assertEqual(manifest.contactinfo['bugurl'], bugurl)
     self.assertEqual(
         manifest.ToXml().toxml(),
-        f"""<?xml version="1.0" ?><manifest><contactinfo bugurl="{bugurl}"/></manifest>""")
+        '<?xml version="1.0" ?><manifest>'
+        f'<contactinfo bugurl="{bugurl}"/>'
+        '</manifest>')