Checks if the string `s` is a valid date string.

    Return True of False.

def chk_date_arg(s):
    """Checks if the string `s` is a valid date string.

    Return True of False."""
    if re_date.search(s) is None:
        return False
    comp = s.split('-')
    try:
        dt = datetime.date(int(comp[0]), int(comp[1]), int(comp[2]))
        return True
    except Exception as e:
        return False