Leetcode 976. Largest Perimeter Triangle

class Solution(object):
    def largestPerimeter(self, A):
        """
        :type A: List[int]
        :rtype: int
        """
        A = sorted(A, reverse=True)
        if len(A) < 3:
            return 0
        i = 0
        while i < len(A) - 2:
            if A[i] < A[i + 1] + A[i + 2]:
                return A[i] + A[i + 1] + A[i + 2]
            else:
                i+=1
        return 0