diff --git a/bob/devtools/bootstrap.py b/bob/devtools/bootstrap.py
index 4b47575b9abbe028e1b3c675d602525cc4bf31b5..fa19efd9864fed661a96e54281009549fb9edd01 100644
--- a/bob/devtools/bootstrap.py
+++ b/bob/devtools/bootstrap.py
@@ -269,9 +269,11 @@ def ensure_miniconda_sh():
             "Just downloaded miniconda3 installer sha256 checksum (%s) does "
             "NOT match expected value (%s). Removing downloaded installer. "
             "A wrong checksum may end up making the CI download too many copies "
-            "and be banned! You must fix this ASAP.",
-            actual_sha256,
-            sha256,
+            "and be banned! You must fix this ASAP."
+            % (
+                actual_sha256,
+                sha256,
+            )
         )