Update add-two-numbers.py

Author: kamyu104

Python/add-two-numbers.py

@@ -32,7 +32,7 @@ def addTwoNumbers(self, l1, l2):
             if l2:
                 val += l2.val
                 l2 = l2.next
-            carry, val = val / 10, val % 10 # val = val//10 if python 3 
+            carry, val = divmod(val, 10)
             current.next = ListNode(val)
             current = current.next