339. Nested List Weight Sum

class Solution(object):
    def depthSum(self, nestedList):
        """
        :type nestedList: List[NestedInteger]
        :rtype: int
        """
        if len(nestedList) == 0: return 0
        stack = []
        sum = 0
        for n in nestedList:
            stack.append((n, 1))
        while stack:
            next, d = stack.pop(0)
            if next.isInteger():
               sum += d * next.getInteger()
            else:
                for i in next.getList():
                    stack.append((i,d+1))
        return sum