pa.py

def is_valid(s):
    stack = []
    for c in s:
        if c == '(' or c == '[':
            stack.append(c)
        elif c == ')':
            if not stack or stack[-1] != '(':
                return False
            stack.pop()
        elif c == ']':
            if not stack or stack[-1] != '[':
                return False
            stack.pop()
    return not stack

t1 = '(()(()))'  # => True
t2 = '(()(())))' # => False
t3 = '(([]))'  # => True
t4 = '(([)])'  # => False 

print(is_valid(t1))
print(is_valid(t2))
print(is_valid(t3))
print(is_valid(t4))