1047. Remove All Adjacent Duplicates In String

class Solution:
    def removeDuplicates(self, S: str) -> str:
        stck = []
        for i in S:
            if len(stck) != 0 and i == stck[-1] :
                stck.pop()
            else:
                stck.append(i)
        return ''.join(map(str,stck))