A simple IRC client written in Python.

irc.py

#
# [2016-03-14] Challenge #258 [Easy] IRC: Making a Connection
# https://www.reddit.com/r/dailyprogrammer/comments/4ad23z/20160314_challenge_258_easy_irc_making_a/
#

import socket

input = """chat.freenode.net:6667
dude1267
dude1267
John Doe"""

# Parse input.
ping = 'PING '.encode()
pong = 'PONG '.encode()
lines = input.split('\n')
host = lines[0].split(':')

# Connect.
client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
client.connect((host[0], int(host[1])))

# Handshake.
client.send(('NICK ' + lines[1] + '\r\n').encode())
client.send(('USER ' + lines[2] + ' 0 * :' + lines[3] + '\r\n').encode())

# Output and ping/pong.
while True:
  data = client.recv(1024)
  print(data)

  if data.startswith(ping):
    resp = data.strip(ping);
    client.send(pong + resp)
    print(pong + resp)