This error means that the client cannot connect to the port on the computer running server script. This can be caused by few things, like lack of routing to the destination or you have a firewall somewhere between your client and the server - it could be on server itself or on the client etc. Note that a server must perform the sequence socket(), bind(), listen(), accept() (possibly repeating the accept() to service more than one client), while a client only needs the sequence socket(), connect(). Also note that the server does not sendall()/recv() on the socket it is listening on but on the new socket returned by accept(). Try the following:
Check if you really have that port listening on the server (this should tell you if your code does what you think it should): based on you OS, but on linux you could do something like netstat -ntulp
Check from the server, if you're accepting the connections to the server: again based on your OS, but telnet LISTENING_IP LISTENING_PORT should do the job
Check if you can access the port of the server from the client , but not using the code: just us the telnet (or appropriate command for your OS) from the client
