diff --git a/exercises/perfect-numbers/perfect_numbers.py b/exercises/perfect-numbers/perfect_numbers.py
index 7ec33bacdf1..df010e7b8c6 100644
--- a/exercises/perfect-numbers/perfect_numbers.py
+++ b/exercises/perfect-numbers/perfect_numbers.py
@@ -1,6 +1,6 @@
-def divisor_generator():
+def divisor_generator(number):
     pass
 
 
-def is_perfect():
+def is_perfect(number):
     pass