diff --git a/aiida_kkr/calculations/kkrnano.py b/aiida_kkr/calculations/kkrnano.py
index ec85baf1..8e201f37 100644
--- a/aiida_kkr/calculations/kkrnano.py
+++ b/aiida_kkr/calculations/kkrnano.py
@@ -212,7 +212,7 @@ def prepare_for_submission(self, tempfolder):
 
         else:
             raise InputValidationError(
-                'Either `strucwithpot` or a `parent_folder` has to be provided.\          If necessary remove one of the inputs.'
+                'Either `strucwithpot` or a `parent_folder` has to be provided. If necessary remove one of the inputs.'
             )
 
         print('passed lattice constant=', passed_lattice_const)