#!/usr/bin/env
import telnetlib
import time
import socket
import sys

TELNET_PORT = 23
TELNET_TIMEOUT = 8

class Telnet(object):

    def __init__(self, username, password, ip_addr, port):
        self.username = username
        self.password = password
        self.ip_addr = ip_addr
        self.port = port
        self.TIMEOUT = 8

    def login(self, remote_conn):
        output = remote_conn.read_until('sername:', self.TIMEOUT)
        remote_conn.write(self.username + '\n')
        output += remote_conn.read_until('ssword:', self.TIMEOUT)
        remote_conn.write(self.password + '\n')
        return output

    def send_command(self, remote_conn, command):
        command = command.rstrip()
        remote_conn.write(command + '\n')
        time.sleep(1)
        return remote_conn.read_very_eager()

    @property
    def telnet_connect(self):
        try:
            return telnetlib.Telnet(self.ip_addr, self.port, self.TIMEOUT)
        except socket.timeout:
            sys.exit('connection timed-out')

def main():

    router1 = Telnet('pyclass', '88newclass', '184.105.247.70', 23)

    remote_conn = router1.telnet_connect
    output = router1.login(remote_conn)

    time.sleep(1)
    output = remote_conn.read_very_eager()

    output = router1.send_command(remote_conn, 'terminal length 0')
    output = router1.send_command(remote_conn, 'show version')
    output = output.strip('show version')
    output = output[:output.rfind('\n')]
    print(output)

    remote_conn.close()

if __name__ == "__main__": main()