python 提供了對底層網路程式設計的socket模組，也提供了諸如urllib、httplib、poplib、ftplib等針對特定功能的程式設計模組。

以下直接貼程式碼測試socket模式使用：

服務端：Server.py

#-*- coding:gbk -*-
'''
Created on 2013-4-30

@author: herong
'''
import threading
from socket import *
import time
class process(threading.Thread):
    '''處理類'''
    __client = None
    __addr = None
    def __init__(self,client,addr):
        threading.Thread.__init__(self)
        self.__client = client
        self.__addr = addr
        print "客戶端%s連線成功!"%(self.__addr[0])
    def run(self ):
        try:
            while True:
                recvData = self.__client.recv(gBufferSize)
                self.__client.send("客戶端%s請求[%s]處理.......\n"%(self.__addr[0],recvData))
                print '處理中......'
                time.sleep(1)
                print '處理完畢.'
                self.__client.send("客戶端%s請求[%s]處理完畢!\n"%(self.__addr[0],recvData))
                self.__client.send("[end]\n")
                
                if recvData == "exit":
                    self.__client.send("伺服器退出!\n")
                    break
        finally:
            self.__client.close()
            
class Server(threading.Thread):
    '''服務端類'''
    __port = None
    __socket = None
    __active = True
    def __init__(self,port=8001,backlog=10):
        threading.Thread.__init__(self)
        self.__port = port
        self.__socket = socket(AF_INET,SOCK_STREAM)
        self.__socket.bind(("",self.__port))
        self.__socket.listen(backlog)
        print "服務開啟，開始接收客戶端請求..."
    def run(self):
        try:
            while self.__active:
                client ,addr = self.__socket.accept()
                print "client:%s,addr:%s"%(client,addr)
                p = process(client ,addr)
                p.setDaemon(True)
                p.start()
        finally:
            self.__socket.close()
            
gBufferSize = 1024
            
if __name__ == '__main__':
    Server(8001,5).start()
 

客戶端：Client.py

#-*- coding:gbk -*-
'''
Created on 2013-4-30

@author: herong
'''
import threading
import sys
from socket import *

class Client(threading.Thread):
    '''客戶端類'''
    __port = None
    __socket = None
    __host = None
    __active = True
    def __init__(self,host,port=8001):
        threading.Thread.__init__(self)
        self.__port = port
        self.__host = host
        self.__socket = socket(AF_INET,SOCK_STREAM)
        self.__socket.connect((self.__host,self.__port))
        print "成功連線服務端%s,埠:%s"%(self.__host,self.__port)
        
    def run(self):
        try:
            while self.__active:
                cmd = raw_input("請輸入請求服務端指令:")
                self.__socket.send(cmd)
                
                while 1:
                    recvData = self.__socket.recv(gBufferSize)
                    print "服務端返回資訊：%s"%(recvData)
                    if cmd == "exit":
                        sys.exit(0)
                    if '[end]'   in recvData:
                        break
        finally:
            self.__socket.close()
           
            
gBufferSize = 1024
            
if __name__ == '__main__':
    Client("127.0.0.1",8001).start()
 

客戶端輸出：

成功連線服務端127.0.0.1,埠:8001
請輸入請求服務端指令:cmd
服務端返回資訊：客戶端127.0.0.1請求[cmd]處理.......

服務端返回資訊：客戶端127.0.0.1請求[cmd]處理完畢!

服務端返回資訊：[end]

請輸入請求服務端指令:

服務端輸出：

服務開啟，開始接收客戶端請求...
client:<socket._socketobject object at 0x0000000002567AD8>,addr:('127.0.0.1', 26097)
客戶端127.0.0.1連線成功!
處理中......
處理完畢.