removebrakets.py

def remove_brackets(text):
    """
    >>> remove_brackets('(())()(((')
    3
    >>> remove_brackets('(()(')
    2
    >>> remove_brackets('()')
    0
    """

    x = 0
    for t in text:
        if t == '(':
            x += 1
        elif t == ')':
            x -= 1

    return max(x, 0)