Python: 括号匹配

s1 = '[{(b)}][[]]'
s2 = '[{(b}][[]]'


def brackets_match(s: str) -> bool:
    opening_brackets = '([{'
    closing_brackets = ')]}'
    nexus = {')': '(', ']': '[', '}': '{'}
    stack = []
    for char in s:
        if char in opening_brackets:
            stack.append(char)
        elif char in closing_brackets:
            if not stack:
                return False
            if stack[-1] == nexus[char]:
                stack.pop()
            else:
                return False
    return stack == []


print(brackets_match(s1))
print(brackets_match(s2))