def parse_packet3(filp):
    """
    Parse PKT3 commands from the given header file.
    """
    packets = []
    for line in filp:
        if not line.startswith('#define '):
            continue

        line = line[8:].strip()

        if line.startswith('PKT3_') and line.find('0x') != -1 and line.find('(') == -1:
            packets.append(line.split()[0])
    return packets