def _can_append_long_entry(e, f):
    """True if f is a FATDirEntry that can follow e. For f to follow e, f and e
    must have the same checksum, and f's ordinal must be one less than e"""
    return (
        f.LDIR_Chksum == e.LDIR_Chksum and
        f.long_name_ordinal() + 1 == e.long_name_ordinal()
    )