diff --git a/sorts/bead_sort.py b/sorts/bead_sort.py
index 2e6fa5161..abc3f81ab 100644
--- a/sorts/bead_sort.py
+++ b/sorts/bead_sort.py
@@ -3,6 +3,8 @@ Bead sort only works for sequences of non-negative integers.
 https://en.wikipedia.org/wiki/Bead_sort
 """
 
+from itertools import pairwise
+
 
 def bead_sort(sequence: list) -> list:
     """