Valid Parentheses LeetCode Solution

Valid Parentheses.py

 class Solution:
    def isValid(self, s: str) -> bool:
        stack=["#"]             # Initializing with a dummy character
        for i in range(len(s)):
            if s[i]=="(" or s[i]=="{" or s[i]=="[":      # If opening bracket, push in stack
                stack.append(s[i])
                continue
            if (s[i]==")" and stack[-1]=="(") or (s[i]=="}" and stack[-1]=="{") or (s[i]=="]" and stack[-1]=="["):
                stack.pop()
            else:
                return False
        if len(stack)!=1:        # If stack is not empty 
            return False
        return True