diff --git a/xclim/sdba/adjustment.py b/xclim/sdba/adjustment.py
index 17d0d2068..253fcd457 100644
--- a/xclim/sdba/adjustment.py
+++ b/xclim/sdba/adjustment.py
@@ -109,7 +109,7 @@ def _check_inputs(cls, *inputs, group):
         ):
             raise ValueError(
                 "Inputs have different multivariate coordinates "
-                f"({set(mv.name for mv in mvcrds)})."
+                f"({{mv.name for mv in mvcrds}})."
             )
 
         if group.prop == "dayofyear" and (