isbalancedpar.py

def isbalanced(string):
    stack = []
    for char in string:
        if char == '(':
            stack.append(char)
        elif char == ')':
            if not stack: # stack empty trying to remove
                return False
            else:
                stack.pop()
    if stack: # end reached but stack not empty
        return False
    return True

print('((()))', isbalanced('((()))'))
print('()(())', isbalanced('()(())'))
print('((((', isbalanced('(((('))
print('))))', isbalanced('))))'))