diff --git a/day15/part2.py b/day15/part2.py
index ba9fa7a..e2510dc 100644
--- a/day15/part2.py
+++ b/day15/part2.py
@@ -1,6 +1,5 @@
 #!/usr/bin/env python3
 import re
-from collections import defaultdict
 
 lines = (x.strip() for x in open("input.txt"))
 # all lines of possible positions