Straightforward python solution

[turing-complet]

class Solution:
    def isValid(self, s):
        """
        :type s: str
        :rtype: bool
        """
        
        stack = []
        
        matching = { "(" : ")", "[" : "]", "{" : "}"}
        
        for c in s:
            if c in matching.keys():
                stack.append(c)
            elif c in matching.values():
                if len(stack) == 0:
                    return False
                if matching[stack[-1]] != c:
                    return False
                else:
                    stack.pop()
                    
        return len(stack) == 0