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How to transfer scapy packets between two python apps

I am trying to transfer scapy packets between two python apps that I wrote. My first python code is sending packet using scapy to the localhost on port 9000. My second python code is listening on the localhost using sockets. But for some reason I can't get the packet on the second code although its shows me that the packet was sent.
Can someone tell me how can I achived this goal?
This is my 'Server':
import socket
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as sock:
sock.bind(("127.0.0.1", 9000))
sock.listen(1)
csock, addr = sock.accept()
data = csock.recv(2048)
print(data)
This is my 'Client' code:
import scapy.all as scapy
def main():
packet = scapy.IP(dst="127.0.0.1") / scapy.TCP(dport=9000) / scapy.Raw(load="data")
scapy.send(packet)
if __name__ == "__main__":
main()
The output is that the client shows that the packet sent and stop running.
And the server stays on the csock, addr = sock.accept

Python Socket does not receive UDP packets

I am currently setting up a python socket for receiving UDP packets via ethernet and have problems with configuring the socket for obtaining data.
The ethernet adapter is configured with a fixed IP address. Using tcpdump, I am able to view the incoming UDP packets (as seen here) on port 4098, IP 192.168.33.30.
I am using the following example code for the socket:
import socket
UDP_IP = "192.168.33.30"
UDP_PORT = 4098
sock = socket.socket(socket.AF_INET, # Internet
socket.SOCK_DGRAM) # UDP
sock.bind((UDP_IP, UDP_PORT))
while True:
data, addr = sock.recvfrom(4096)
print("received message: %s" % data)
Unfortunately, there is no data return, even if the UDP packets are constantly send to the device. I am using a NVIDIA Jetson NX with Ubuntu 18.04.
So far I have checked the firewall and disabled it completely, but things did not change.
I am thankful for every advice on further troubleshooting!

A request to send or receive data was disallowed because the socket is not connected in Python

I'm trying to make a console chat app in python using socket library.
Whenever I send a message to the server, the server code crashes with the following message:
OSError: [WinError 10057] A request to send or receive data was disallowed because the socket is not connected and (when sending on a datagram socket using a sendto call) no address was supplied
Server code
import socket
HOST = socket.gethostbyname(socket.gethostname()) # get the ip address of PC
PORT = 5050
ADDRESS = (HOST, PORT)
socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
socket.bind(ADDRESS)
while True:
socket.listen()
conn, addr = socket.accept()
print(f"Connected by {addr}")
while True:
data = conn.recv(64)
print(data.decode('utf-8'))
socket.send(data)
Client code
import socket
HOST = socket.gethostbyname(socket.gethostname()) # get the ip address of PC
PORT = 5050
ADDRESS = (HOST, PORT)
socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
socket.connect(ADDRESS)
while True:
msg = input("Enter your message")
socket.send(msg.encode('utf-8'))
data = socket.recv(64)
print(data.decode('utf-8'))
What I am trying to achieve is whenever I send a message to the server, the client script should print the sent message. How can I fix that?

You're attempting to send data to your own server socket. You instead want to send to the client that you accepted.
socket.send(data)
Should be:
conn.send(data)
If you think about it, if you had multiple clients, how would you send data to a specific client? By using the socket that accept gave you.
As a side note, you probably don't want to import the module as socket, and also call your variable socket. It's fine here, but if you were to make a more complicated project, you may accidentally refer to the object when you meant to refer to the module. I'd rename the socket object to sock or server_socket to avoid shadowing.

binding a UDP port and listening for connections

When I try to ping a Minecraft server via LAN, the documents say the following:
In Singeplayer there is a function called "Open to LAN". Minecraft (in the serverlist) binds a UDP port and listens for connections to 224.0.2.60:4445 (Yes, that is the actual IP, no matter in what network you are or what your local IP Address is)" ....... client side, bind a UDP socket and listen for connections. You can use a MulticastSocket for that.
I tried to implement this in Python in the following way:
import socket
UDP_IP = "224.0.2.60"
UDP_PORT = 4445
sock = socket.socket(socket.AF_INET, # Internet
socket.SOCK_DGRAM) # UDP
sock.bind((UDP_IP, UDP_PORT))
while True:
data, addr = sock.recvfrom(1024) # buffer size is 1024 bytes
print("received message: %s" % data)
Which gave me an OSError: [WinError 10049] error.
Please help :( I have no idea what's wrong with my code.
By the way, sending packets to that port works, and the fake server shows up on the Minecraft app.

You cannot bind to a multicast address like that. It is somewhat more involved.
I recommend to read this article that explains all the details of using multicast with Python.

How to send socket message when Server has a preset initial response?

I'm making python binds for Blackmagic's Ethernet Control Protocol ( as documented in https://documents.blackmagicdesign.com/UserManuals/HyperDeckManual.pdf?_v=1528269592000 , page 60). Simple socket connection seems to fail however, because every commands gets rejected with the server's greeting.
This protocol documents how software can communicate with certain blackmagic devices, in this case, Blackmagic's hyperdeck, the device runs a TCP server constantly listening on port 9993, on cmd I can simply telnet to it and issue commands, you'd it expect it to be as straightforward in python, however every command gets ignored for the server's greeting message, the device's information. I have been doing socket's for at least 3 months now and i've tried several methods of code, and all seem to fail.
For the most trivial test i've used:
import socket
HOST = "device's ip"
PORT = 9993
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((HOST, PORT))
s.sendall(b'play')
data = s.recv(1024)
print(data)
and a modified version to try to repeat the command:
import socket
import time
HOST = "device's ip"
PORT = 9993
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((HOST, PORT))
s.sendall(b'play')
data = s.recv(1024)
time.sleep(2)
s.sendall(b'play')
It should start video playback, as documented, and as occurs when I issue the command thru telnet, however the command is completely ignored and data always equals to: b'500 connection info:\r\nprotocol version: 1.9\r\nmodel: HyperDeck Studio Mini\r\n\r\n' , the server's greeting message in byte form, it should instead be 200 ok or some sort of error / acknowledged message, as documented.
This is incredibly annoying and i've thought of using subprocess and issuing commands thru cmd as an alternative, but something tells me there's an easier workaround.