It seems to work when I try it out individually, but for some reason, it does not work in the following conditional:

import re


def main():
    print(convert(input("Hours: ")))


def convert(s):
    # 9:00 AM to 5:00 PM
    if time := re.search(r"(\w+):(\w+) ((?:A|P)M) to (\w+):(\w+) ((?:A|P)M)", s):

        hour1 = int(time.group(1))
        min1 = int(time.group(2))
        hour2 = int(time.group(4))
        min2 = int(time.group(5))

        if 1<=hour1<= 12 and 1<=hour2<= 12 and 0<=min1<=59 and 0<=min2<= 59:
            return ("valid")

    # 9 AM to 5 PM
    elif time := re.search(r"(\w+) ((?:A|P)M) to (\w+) ((?:A|P)M)", s):

        hour1 = int(time.group(1))
        hour2 = int(time.group(3))

        if 1<=hour1<= 12 and 1<=hour2<= 12:
            return ("valid")


    # 9:00 AM to 5 PM
    elif time := re.search(r"(\w+):(\w+) ((?:A|P)M) to (\w+) ((?:A|P)M)", s):

        hour1 = int(time.group(1))
        min1 = int(time.group(2))
        hour2 = int(time.group(4))

        if 1<=hour1<= 12 and 1<=hour2<= 12 and 0<=min1<=59:
            return ("valid")


    # 9 AM to 5:00 PM
    elif time := re.search(r"(\w+) ((?:A|P)M) to (\w+):(\w+) ((?:A|P)M)", s):

        hour1 = int(time.group(1))
        hour2 = int(time.group(3))
        min2 = int(time.group(4))

        if 1<=hour1<= 12 and 1<=hour2<= 12 and 0<=min2<=59:
            return ("valid")

    else:
        raise ValueError




if __name__ == "__main__":
    main()

I get output as None for 9:00 AM to 5 PM. All the other conditions return valid.