Refactor Contains Duplicate

Author: jinbeom

contains-duplicate/kayden.py

@@ -2,5 +2,4 @@
 # 공간복잡도: O(N)
 class Solution:
     def containsDuplicate(self, nums: List[int]) -> bool:
-        unique_nums = set(nums)
-        return len(unique_nums) != len(nums)
+        return len(set(nums)) != len(nums)