diff --git a/test/candidate_space/test_candidate_space.py b/test/candidate_space/test_candidate_space.py
index 8c0d2351..523f42d7 100644
--- a/test/candidate_space/test_candidate_space.py
+++ b/test/candidate_space/test_candidate_space.py
@@ -5,6 +5,7 @@
 from more_itertools import one
 
 import petab_select
+
 # from petab_select.candidate_space import (
 #    BackwardCandidateSpace,
 #    BruteForceCandidateSpace,