Python recursion - boolean

Question

I'm still quite new to recursion and unable to figure out how to return a single boolean in my code. When left and right executes each will produce True or False, but how do i return a single boolean based on bool from left and bool from right?

def is_regex(s: str) -> bool:

    bar_and_nodes = []
    parentheses = []
    node = 0

    if len(s) == 1:
        return s == '0' or s == '1' or s == '2' or s == 'e'

    #omitted code

    if s[-1] == ')':

        # omitted code

        if node > len(s) // 2:
            split = s[1:-1].rsplit(s[node], 1)
            left = is_regex(split[0])
            right = is_regex(split[1]) 
        else:
            split = s[1:-1].split(s[node], 1)
            left = is_regex(split[0])
            right = is_regex(split[1])

        # want to return left and right

Thanks!

Answer 1

You need to return an and on left and right because if either left or right is not a regex, the whole thing is not a regex.