A failure of a telnet client.

utelnet.py

# telnet program example
import socket, select, sys, _thread

class uTelnet:
    # Automatically initialized class variables
    # Status variables
    connected = False
    last_response = ""

    # Class methods
    def __init__(self, server="rainmaker.wunderground.com", port=23):
        self.server = server
        self.port = port

    def connect(self):
        self.conn = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        self.conn.connect((self.server, self.port))
        self.connected = True

    def send_quit(self, message="Goodbye..."):
        self.send_cmd("QUIT", message)

    def get_response(self):
        return self.conn.recv(1024).decode("utf-8")

    def send_cmd(self, cmd, message):
        command = "{} {}\r\n".format(cmd, message).encode("utf-8")
        self.conn.send(command)

    def send_msg(self, message):
        command = "{}".format(message).encode("utf-8")
        self.conn.send(command)

# End of uTelnet class


# _thread target function to print responses
def print_response():
    while(client.connected):
        client.last_response = client.get_response()
        if(client.last_response != ''):
            if "Closing Link" in client.last_response: #  Server said goodbye
                client.connected = False  # So we're disconnected now, thread ends.
            print("{}".format(client.last_response.strip()))  # Print the response.

# socket conn.receive blocks the program until a response is received
# to prevent blocking program execution, receive should be threaded
def go():
    cmd = ""  # Start with an empty string
    client.connect()  # Connect to the server

    _thread.stack_size(10*1024)  # Get a 10KB Stack
    enginethread = _thread.start_new_thread("uTelnet", print_response, ())
    _thread.stack_size(4*1024)  # Go back to 4KB

    # Loop until quit, _thread will handle printing.
    while(cmd != "/quit"):
        cmd = input(" ")
        if cmd == "/quit":
            client.send_quit()
        client.send_msg(cmd)

# End of functions

client = uTelnet()  # Create the client object so it is a global to the REPL