def globify_date(filename):
    """Replace date formats with single character wildcards"""
    filename = filename.replace('%Y', '????')
    filename = filename.replace('%m', '??')
    filename = filename.replace('%d', '??')
    filename = filename.replace('%H', '??')
    filename = filename.replace('%M', '??')
    filename = filename.replace('%S', '??')
    return filename
