python asyncoreでechoサーバーいろいろ見たけどよく分からない。

gistfile1.py

import asyncore
import socket

class EchoHandler(asyncore.dispatcher):

    def __init__(self, sock):
        asyncore.dispatcher.__init__(self, sock=sock)
        self.send('welcome')
        return

    def handle_read(self):
        data = self.recv(8192)
        if data:
            if data.rstrip("\r\n") == '':
                self.send('disconnect')
                self.close()
            self.send(data)

class Server(asyncore.dispatcher):

    def __init__(self, host, port):
        asyncore.dispatcher.__init__(self)
        self.create_socket(socket.AF_INET, socket.SOCK_STREAM)
        self.set_reuse_addr()
        self.bind((host, port))
        self.listen(1)

    def handle_accept(self):
        pair = self.accept()
        if pair:
            sock, addr = pair
            handler = EchoHandler(sock)

server = Server('localhost', 8080)
while asyncore.socket_map:
    asyncore.loop(timeout=1, count=1)