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Lab 1 - Displaying Output of Show Commands - Interactive
**********************************************************

from telnetlib import Telnet

usercmd = input('Enter the Command : ')
usercmd = usercmd + '\n'
telsession = Telnet('172.25.1.1')
telsession.write(b'khawar\n')
telsession.write(b'cisco\n')
telsession.write(b'terminal length 0\n')
telsession.write(usercmd.encode('ascii'))
telsession.write(b'exit\n')
print(telsession.read_all().decode('ascii'))

Notes:

- Invoke the Telnet Function from the built-in telnetlib
- usercmd is a variable that will store the input from the input function.
- telsession is a variable that points to the Telnet Function to the IP address of 172.25.1.1. You need to use it everytime you want to read or write from this session.
- Send commands to the session using the Telnet function uses 2 methods:
	- telsession.write(b'xxxxxx\n') Send the command within the ' ' in the ASCII format (b' ')
	- telsession.write(usercmd.encode('ascii') If a variable needs to be sent, use the encode('ascii') method
- telsession.read_all().decode('ascii') reads the terminal output for the entire session.
- print function prints the output on the screen

******************************************************************
Lab 2 - Displaying Output of Show Commands - Interactive Login
******************************************************************

from telnetlib import Telnet

HOST = input ('IP Address of device: ')
USER = input ('Enter your Username: ')
USER = USER + '\n'
PASS = input ('Enter the password: ')
PASS = PASS + '\n'
usercmd = input('Enter the Command : ')
usercmd = usercmd + '\n'
telsession = Telnet(HOST)
telsession.write(USER.encode('ascii'))
telsession.write(PASS.encode('ascii'))
telsession.write(b'terminal length 0\n')
telsession.write(usercmd.encode('ascii'))
telsession.write(b'exit\n')
print(telsession.read_all().decode('ascii'))

**********************************************************
Lab 3 - Configuring Interface using Telnet - Interactive
**********************************************************

from telnetlib import Telnet

HOST = input ('IP Address of device: ')
USER = input ('Enter your Username: ')
USER = USER + '\n'
PASS = input ('Enter the password: ')
PASS = PASS + '\n'
intid = input('Enter the Interface to be configured "Loopback99,E0/0 etc" : ')
intcmd = 'interface ' + intid + '\n'
ipaddr = input('Enter the IP Address for the Interface: ')
smask =  input('Enter the Subnet Mask: ')
ipcmd = 'ip address ' + ipaddr + ' ' + smask + '\n'
telsession = Telnet(HOST)
telsession.write(USER.encode('ascii'))
telsession.write(PASS.encode('ascii'))
telsession.write(b'terminal length 0\n')
telsession.write(b'config t\n')
telsession.write(intcmd.encode('ascii'))
telsession.write(ipcmd.encode('ascii'))
telsession.write(b'end\n')
telsession.write(b'sh ip int brief\n')
telsession.write(b'exit\n')
telsession.read_until(b'#end')
print (telsession.read_all().decode('ascii'))