import re


def find_startend_time(s):
    """
    Find starttime and endtime from a given string
    """
    starttime, endtime = '', ''
    ts = re.findall(r'(\d+\:\d+\s?(?:AM|PM|am|pm|A.M.|P.M.|a.m.|p.m.))', s)
    if len(ts) == 1:
        starttime = ts[0]
        endtime = ''
    elif len(ts) == 2:
        starttime = ts[0]
        endtime = ts[1]
    return starttime, endtime