b-davis login:
Password:
Last login: Mon Aug 29 20:28:24 EDT 2016 from localhost on pts/5

import telnetlib
import re
pw = "p@ssw0rd"
user = "bdavis"
regex = [
    b"[Ll]ogin.",  # b"[Ll]ogin" works here
    b"[Pp]assword",
    b'>',
    b'#']

tn = telnetlib.Telnet("1.2.3.4")

while type(tn.get_socket()) is not int:
    result = tn.expect(regex, 5)  # Retrieve send information
    s = result[2].decode()

    if re.search("[Ll]ogin$",s) is not None:
        print("Do login stuff")
        print(result)
        tn.write((user + "n").encode())  # Send Username
    elif re.search("[Pp]assword",s) is not None:
        print("Do password stuff")
        tn.write((pw + "n").encode())  # Send Password
    elif re.search('>',s) is not None:
        print("Do Cisco User Stuff")
        tn.write(b"exitn")  # exit telnet
        tn.close()
    elif re.search('#',s) is not None:
        print("Do Cisco Admin Stuff")
    else:
        print("I Don't understand this, help me:")
        print(s)
        tn.close()