telnet.py

#!/usr/bin/env python3
import sys
import socket
from contextlib import closing

def check_socket(host, port):
    with closing(socket.socket(socket.AF_INET, socket.SOCK_STREAM)) as sock:
        sock.settimeout(1)
        if sock.connect_ex((host, port)) == 0:
            print("Port is open")
        else:
            print("Port is not open")

if len(sys.argv) != 3:
    print("Usage: %s <host> <port>" % sys.argv[0])
    sys.exit()

check_socket(sys.argv[1],int(sys.argv[2]))