diff --git a/tangostationcontrol/toolkit/generate_caltable_from_lofar1.py b/tangostationcontrol/toolkit/generate_caltable_from_lofar1.py
index 473b4e2bc2cea6562d0ec73df69b0f2b273166f9..fa58d936821bccd2778698fd0a4fce723487250c 100755
--- a/tangostationcontrol/toolkit/generate_caltable_from_lofar1.py
+++ b/tangostationcontrol/toolkit/generate_caltable_from_lofar1.py
@@ -81,12 +81,12 @@ class LOFAR2CalTables:
                 calvalues_y = lofar1_caltable_data[:, antenna_nr * 2 + 1]
 
                 # validate
-                assert len(calvalues_x) == 512, (
-                    "Expected calibration values for 512 subbands"
-                )
-                assert len(calvalues_y) == 512, (
-                    "Expected calibration values for 512 subbands"
-                )
+                assert (
+                    len(calvalues_x) == 512
+                ), "Expected calibration values for 512 subbands"
+                assert (
+                    len(calvalues_y) == 512
+                ), "Expected calibration values for 512 subbands"
 
                 # write to LOFAR2
                 table.antennas[f"{antenna_name_prefix}{antenna_nr:02}"] = (