balance_brackets.py

def is_balance(s) -> bool:
    open, close = '<{[(', ')]}>'
    brackets = dict(zip(open, close[::-1]))
    # print( brackets )

    stack = []
    for c in s:
        if c in brackets:  # open; O(1)
            stack.append(c)  # .push
        elif c in brackets.values():  # close; O(4)
            if not stack:  # .is_empty
                return False
            if c != brackets[stack[-1]]:  # .peek
                return False
            stack.pop()  # .pop
        else:  # support other string inside brackets
            pass

    return not stack


if __name__ == '__main__':
    # is_balance(''); import sys; sys.exit(0)
    assert is_balance('') is True
    assert is_balance('()') is True
    assert is_balance('[]') is True
    assert is_balance('{}') is True
    assert is_balance('<>') is True

    assert is_balance('<{[()]}>') is True
    assert is_balance('<>{[()]}') is True
    assert is_balance('<>{[()]}<>') is True
    assert is_balance('<{}>[()]') is True
    assert is_balance('<{}>[(){[]}]') is True

    for c in '<>{}[]()':
        assert is_balance(c) is False
    assert is_balance('[(]') is False
    assert is_balance('{)}') is False
    assert is_balance('{}(') is False
    assert is_balance('{})') is False
    assert is_balance('({}') is False
    assert is_balance('){}') is False