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import socket

src_ip = '127.0.0.1'
dest_ip = '127.0.0.1'
src_port = 8088
dest_port = 80

raw_socket = socket.socket(socket.AF_INET, socket.SOCK_RAW, socket.IPPROTO_TCP)
raw_socket.setsockopt(socket.IPPROTO_IP, socket.IP_HDRINCL, 1)

ip_header = b"\x45\x00\x00\x40" # version, ihl, tos, Total length
ip_header += b"\x00\x00\x40\x00" # id, IP flags, fragment offset
ip_header += b"\x40\x06\x00\x00" # TTL, protocol, header checksum
ip_header += socket.inet_aton(src_ip) # source address
ip_header += socket.inet_aton(dest_ip) # destination address

tcp_header = src_port.to_bytes(2, 'big') + dest_port.to_bytes(2, 'big') # source port, destination port
tcp_header += b"\x00\x00\x00\x00" # seq number
tcp_header += b"\x00\x00\x00\x00" # ack number
tcp_header += b"\x50\x02\xff\xff" # offset, reserved, TCP flags, window
tcp_header += b"\x00\x00\x00\x00" # checksum, urgent pointer

raw_socket.sendto(ip_header + tcp_header, (dest_ip, dest_port))

response, _ = raw_socket.recvfrom(4096)
if response:
    tcp_flag = int.from_bytes(response[33:34], "big")
    if tcp_flag == 18: # SYN/ACK
        print(f"{dest_port} is opened")
    elif tcp_flag == 20: # RST
        print(f"{dest_port} is closed")