def flirt(message):
    if len(message) <= 1:
        return ''
    for sep in '.!?':
        s, sepfound, after = message.partition(sep)
        numspace = len(s) - len(s.lstrip())
        s = ' ' * numspace + \
            random.choice(PHRASES).format(s=s.lstrip().lower(), sep=sepfound)
        return s + flirt(after)
    return message