682. LeetCode Solution. Baseball Game

class Solution:
    def calPoints(self, operations: List[str]) -> int:
        L = []

        for i in operations:
            if i.isdigit() or (i.startswith('-') and i[1:].isdigit()):
                i = int(i)
            if i == "+":
                L.append(L[-1] + L[-2])
            elif i == "D":
                L.append(L[-1]*2)
            elif i == "C":
                L.pop()
            else:
                L.append(i)
        
        return sum(L)