sol3.py

from collections import deque

class Solution:
    def isValid(self, s: str) -> bool:
        l = deque()
        for i in range(len(s)):
            if s[i] in "[({":
                l.append(s[i])
            elif s[i] in "})]":
                if len(l) == 0:
                    return False
                cc = l.pop()
                if s[i] == "]" and cc != "[":
                    return False
                if s[i] == ")" and cc != "(":
                    return False
                if s[i] == "}" and cc != "{":
                    return False
        
        
        return len(l) == 0