Contains Duplicate Python Solution with Tests

lcpy gen -n 217   # by problem number
lcpy gen -s contains_duplicate   # by problem name

Input: nums = [1,2,3,1]
Output: true

Input: nums = [1,2,3,4]
Output: false

Input: nums = [1,1,1,3,3,4,3,2,4,2]
Output: true

class Solution:
    # Time: O(n)
    # Space: O(n)
    def contains_duplicate(self, nums: list[int]) -> bool:
        seen = set()
        for num in nums:
            if num in seen:
                return True
            seen.add(num)
        return False