import socket

sk = socket.socket()
sk.bind(("127.0.0.1",8080))
sk.listen(5)

conn,address = sk.accept()
sk.sendall(bytes("Hello world",encoding="utf-8"))

import socket

obj = socket.socket()
obj.connect(("127.0.0.1",8080))

ret = str(obj.recv(1024),encoding="utf-8")
print(ret)

def bind(self, address): # real signature unknown; restored from __doc__
        """
        bind(address)
        
        Bind the socket to a local address.  For IP sockets, the address is a
        pair (host, port); the host must refer to the local host. For raw packet
        sockets the address is a tuple (ifname, proto [,pkttype [,hatype]])
        """
'''将套接字绑定到本地地址。是一个IP套接字的地址对(主机、端口),主机必须参考本地主机。'''
        pass

    def close(self): # real signature unknown; restored from __doc__
        """
        close()
        
        Close the socket.  It cannot be used after this call.
        """
        '''关闭socket'''
        pass

    def connect(self, address): # real signature unknown; restored from __doc__
        """
        connect(address)
        
        Connect the socket to a remote address.  For IP sockets, the address
        is a pair (host, port).
        """
        '''将套接字连接到远程地址。IP套接字的地址'''
        pass

    def connect_ex(self, address): # real signature unknown; restored from __doc__
        """
        connect_ex(address) -> errno
        
        This is like connect(address), but returns an error code (the errno value)
        instead of raising an exception when an error occurs.
        """
        pass

    def detach(self): # real signature unknown; restored from __doc__
        """
        detach()
        
        Close the socket object without closing the underlying file descriptor.
        The object cannot be used after this call, but the file descriptor
        can be reused for other purposes.  The file descriptor is returned.
        """
'''关闭套接字对象没有关闭底层的文件描述符。'''
        pass

    def fileno(self): # real signature unknown; restored from __doc__
        """
        fileno() -> integer
        
        Return the integer file descriptor of the socket.
        """
        '''返回整数的套接字的文件描述符。'''
        return 0

    def getpeername(self): # real signature unknown; restored from __doc__
        """
        getpeername() -> address info
        
        Return the address of the remote endpoint.  For IP sockets, the address
        info is a pair (hostaddr, port).
            """
        '''返回远程端点的地址。IP套接字的地址'''
        pass

    def getsockname(self): # real signature unknown; restored from __doc__
        """
        getsockname() -> address info
        
        Return the address of the local endpoint.  For IP sockets, the address
        info is a pair (hostaddr, port).
        """
        '''返回远程端点的地址。IP套接字的地址'''
        pass

    def getsockopt(self, level, option, buffersize=None): # real signature unknown; restored from __doc__
        """
        getsockopt(level, option[, buffersize]) -> value
        
        Get a socket option.  See the Unix manual for level and option.
        If a nonzero buffersize argument is given, the return value is a
        string of that length; otherwise it is an integer.
        """
        '''得到一个套接字选项'''
        pass

    def gettimeout(self): # real signature unknown; restored from __doc__
        """
        gettimeout() -> timeout
        
        Returns the timeout in seconds (float) associated with socket 
        operations. A timeout of None indicates that timeouts on socket 
        operations are disabled.
        """
        '''返回的超时秒数(浮动)与套接字相关联'''
        return timeout

    def ioctl(self, cmd, option): # real signature unknown; restored from __doc__
        """
        ioctl(cmd, option) -> long
        
        Control the socket with WSAIoctl syscall. Currently supported 'cmd' values are
        SIO_RCVALL:  'option' must be one of the socket.RCVALL_* constants.
        SIO_KEEPALIVE_VALS:  'option' is a tuple of (onoff, timeout, interval).
        """
        return 0

    def listen(self, backlog=None): # real signature unknown; restored from __doc__
        """
        listen([backlog])
        
        Enable a server to accept connections.  If backlog is specified, it must be
        at least 0 (if it is lower, it is set to 0); it specifies the number of
        unaccepted connections that the system will allow before refusing new
        connections. If not specified, a default reasonable value is chosen.
        """
        '''使服务器能够接受连接。'''
        pass

    def recv(self, buffersize, flags=None): # real signature unknown; restored from __doc__
        """
        recv(buffersize[, flags]) -> data
        
        Receive up to buffersize bytes from the socket.  For the optional flags
        argument, see the Unix manual.  When no data is available, block until
        at least one byte is available or until the remote end is closed.  When
        the remote end is closed and all data is read, return the empty string.
        """
'''当没有数据可用,阻塞,直到至少一个字节是可用的或远程结束之前关闭。'''
        pass

    def recvfrom(self, buffersize, flags=None): # real signature unknown; restored from __doc__
        """
        recvfrom(buffersize[, flags]) -> (data, address info)
        
        Like recv(buffersize, flags) but also return the sender's address info.
        """
        pass

    def recvfrom_into(self, buffer, nbytes=None, flags=None): # real signature unknown; restored from __doc__
        """
        recvfrom_into(buffer[, nbytes[, flags]]) -> (nbytes, address info)
        
        Like recv_into(buffer[, nbytes[, flags]]) but also return the sender's address info.
        """
        pass

    def recv_into(self, buffer, nbytes=None, flags=None): # real signature unknown; restored from __doc__
        """
        recv_into(buffer, [nbytes[, flags]]) -> nbytes_read
        
        A version of recv() that stores its data into a buffer rather than creating 
        a new string.  Receive up to buffersize bytes from the socket.  If buffersize 
        is not specified (or 0), receive up to the size available in the given buffer.
        
        See recv() for documentation about the flags.
        """
        pass

    def send(self, data, flags=None): # real signature unknown; restored from __doc__
        """
        send(data[, flags]) -> count
        
        Send a data string to the socket.  For the optional flags
        argument, see the Unix manual.  Return the number of bytes
        sent; this may be less than len(data) if the network is busy.
        """
        '''发送一个数据字符串到套接字。'''
        pass

    def sendall(self, data, flags=None): # real signature unknown; restored from __doc__
        """
        sendall(data[, flags])
        
        Send a data string to the socket.  For the optional flags
        argument, see the Unix manual.  This calls send() repeatedly
        until all data is sent.  If an error occurs, it's impossible
        to tell how much data has been sent.
        """
        '''发送一个数据字符串到套接字，直到所有数据发送完成'''
        pass

    def sendto(self, data, flags=None, *args, **kwargs): # real signature unknown; NOTE: unreliably restored from __doc__ 
        """
        sendto(data[, flags], address) -> count
        
        Like send(data, flags) but allows specifying the destination address.
        For IP sockets, the address is a pair (hostaddr, port).
        """
        pass

    def setblocking(self, flag): # real signature unknown; restored from __doc__
        """
        setblocking(flag)
        
        Set the socket to blocking (flag is true) or non-blocking (false).
        setblocking(True) is equivalent to settimeout(None);
        setblocking(False) is equivalent to settimeout(0.0).
        """
'''是否阻塞（默认True），如果设置False，那么accept和recv时一旦无数据，则报错。'''
        pass

    def setsockopt(self, level, option, value): # real signature unknown; restored from __doc__
        """
        setsockopt(level, option, value)
        
        Set a socket option.  See the Unix manual for level and option.
        The value argument can either be an integer or a string.
        """
        pass

    def settimeout(self, timeout): # real signature unknown; restored from __doc__
        """
        settimeout(timeout)
        
        Set a timeout on socket operations.  'timeout' can be a float,
        giving in seconds, or None.  Setting a timeout of None disables
        the timeout feature and is equivalent to setblocking(1).
        Setting a timeout of zero is the same as setblocking(0).
        """
        pass

    def share(self, process_id): # real signature unknown; restored from __doc__
        """
        share(process_id) -> bytes
        
        Share the socket with another process.  The target process id
        must be provided and the resulting bytes object passed to the target
        process.  There the shared socket can be instantiated by calling
        socket.fromshare().
        """
        return b""

    def shutdown(self, flag): # real signature unknown; restored from __doc__
        """
        shutdown(flag)
        
        Shut down the reading side of the socket (flag == SHUT_RD), the writing side
        of the socket (flag == SHUT_WR), or both ends (flag == SHUT_RDWR).
        """
        pass

    def _accept(self): # real signature unknown; restored from __doc__
        """
        _accept() -> (integer, address info)
        
        Wait for an incoming connection.  Return a new socket file descriptor
        representing the connection, and the address of the client.
        For IP sockets, the address info is a pair (hostaddr, port).
        """
        pass

import  socketserver
服务端

class Myserver(socketserver.BaseRequestHandler):

    def handle(self):

        conn = self.request
        conn.sendall(bytes("你好，我是机器人",encoding="utf-8"))
        while True:
            ret_bytes = conn.recv(1024)
            ret_str = str(ret_bytes,encoding="utf-8")
            if ret_str == "q":
                break
            conn.sendall(bytes(ret_str+"你好我好大家好",encoding="utf-8"))

if __name__ == "__main__":
    server = socketserver.ThreadingTCPServer(("127.0.0.1",8080),Myserver)
    server.serve_forever()

客户端

import socket

obj = socket.socket()

obj.connect(("127.0.0.1",8080))

ret_bytes = obj.recv(1024)
ret_str = str(ret_bytes,encoding="utf-8")
print(ret_str)

while True:
    inp = input("你好请问您有什么问题？ \n >>>")
    if inp == "q":
        obj.sendall(bytes(inp,encoding="utf-8"))
        break
    else:
        obj.sendall(bytes(inp, encoding="utf-8"))
        ret_bytes = obj.recv(1024)
        ret_str = str(ret_bytes,encoding="utf-8")
        print(ret_str)

服务端

import socket

sk = socket.socket()

sk.bind(("127.0.0.1",8080))
sk.listen(5)

while True:
    conn,address = sk.accept()
    conn.sendall(bytes("欢迎光临我爱我家",encoding="utf-8"))

    size = conn.recv(1024)
    size_str = str(size,encoding="utf-8")
    file_size = int(size_str)

    conn.sendall(bytes("开始传送", encoding="utf-8"))

    has_size = 0
    f = open("db_new.jpg","wb")
    while True:
        if file_size == has_size:
            break
        date = conn.recv(1024)
        f.write(date)
        has_size += len(date)

    f.close()

客户端

import socket
import os

obj = socket.socket()

obj.connect(("127.0.0.1",8080))

ret_bytes = obj.recv(1024)
ret_str = str(ret_bytes,encoding="utf-8")
print(ret_str)

size = os.stat("yan.jpg").st_size
obj.sendall(bytes(str(size),encoding="utf-8"))

obj.recv(1024)

with open("yan.jpg","rb") as f:
    for line in f:
        obj.sendall(line)

import socket
ip_port = ('127.0.0.1',9999)
sk = socket.socket(socket.AF_INET,socket.SOCK_DGRAM,0)
sk.bind(ip_port)

while True:
    data = sk.recv(1024)
    print data




import socket
ip_port = ('127.0.0.1',9999)

sk = socket.socket(socket.AF_INET,socket.SOCK_DGRAM,0)
while True:
    inp = input('数据：').strip()
    if inp == 'exit':
        break
    sk.sendto(bytes(inp,encoding = "utf-8"),ip_port)

sk.close()

importsocketdefhandle_request(client):    buf =client.recv(1024)    client.send("HTTP/1.1 200 OK\r\n\r\n")    client.send("Hello, World")defmain():    sock =socket.socket(socket.AF_INET, socket.SOCK_STREAM)    sock.bind(('localhost',8080))    sock.listen(5)    whileTrue:        connection, address =sock.accept()        handle_request(connection)        connection.close()if__name__ =='__main__':  main()

Windows Python：    提供： selectMac Python：    提供： selectLinux Python：    提供： select、poll、epoll

句柄列表11, 句柄列表22, 句柄列表33=select.select(句柄序列1, 句柄序列2, 句柄序列3, 超时时间)参数： 可接受四个参数（前三个必须）返回值：三个列表select方法用来监视文件句柄，如果句柄发生变化，则获取该句柄。1、当 参数1序列中的句柄发生可读时（accetp和read），则获取发生变化的句柄并添加到 返回值1序列中2、当 参数2序列中含有句柄时，则将该序列中所有的句柄添加到 返回值2序列中3、当 参数3序列中的句柄发生错误时，则将该发生错误的句柄添加到 返回值3序列中4、当 超时时间 未设置，则select会一直阻塞，直到监听的句柄发生变化5、当 超时时间 ＝ 1时，那么如果监听的句柄均无任何变化，则select会阻塞 1秒，之后返回三个空列表，如果监听的句柄有变化，则直接执行。

import socket
import select


sk1 = socket.socket()
sk1.bind(("127.0.0.1",8001))
sk1.listen()

sk2 = socket.socket()
sk2.bind(("127.0.0.1",8002))
sk2.listen()

sk3 = socket.socket()
sk3.bind(("127.0.0.1",8003))
sk3.listen()

li = [sk1,sk2,sk3]

while True:
    r_list,w_list,e_list = select.select(li,[],[],1) # r_list可变化的
    for line in r_list: 
        conn,address = line.accept()
        conn.sendall(bytes("Hello World !",encoding="utf-8"))

服务端：
sk1 = socket.socket()
sk1.bind(("127.0.0.1",8001))
sk1.listen()

inpu = [sk1,]

while True:
    r_list,w_list,e_list = select.select(inpu,[],[],1)
    for sk in r_list:
        if sk == sk1:
            conn,address = sk.accept()
            inpu.append(conn)
        else:
            try:
                ret = str(sk.recv(1024),encoding="utf-8")
                sk.sendall(bytes(ret+"hao",encoding="utf-8"))
            except Exception as ex:
                inpu.remove(sk)

客户端
import socket

obj = socket.socket()

obj.connect(('127.0.0.1',8001))

while True:
    inp = input("Please(q\退出):\n>>>")
    obj.sendall(bytes(inp,encoding="utf-8"))
    if inp == "q":
        break
    ret = str(obj.recv(1024),encoding="utf-8")
    print(ret)

服务端：
import socket
sk1 = socket.socket()
sk1.bind(("127.0.0.1",8001))
sk1.listen()
inputs = [sk1]
import select
message_dic = {}
outputs = []
while True:

    r_list, w_list, e_list = select.select(inputs,[],inputs,1)
    print("正在监听的socket对象%d" % len(inputs))
    print(r_list)
    for sk1_or_conn in r_list:
        if sk1_or_conn == sk1:
            conn,address = sk1_or_conn.accept()
            inputs.append(conn)
            message_dic[conn] = []
        else:
            try:
                data_bytes = sk1_or_conn.recv(1024)
                data_str = str(data_bytes,encoding="utf-8")
                sk1_or_conn.sendall(bytes(data_str+"好",encoding="utf-8"))
            except Exception as ex:
                inputs.remove(sk1_or_conn)
            else:
                data_str = str(data_bytes,encoding="utf-8")
                message_dic[sk1_or_conn].append(data_str)
                outputs.append(sk1_or_conn)
        for conn in w_list:
            recv_str = message_dic[conn][0]
            del message_dic[conn][0]
            conn.sendall(bytes(recv_str+"好",encoding="utf-8"))
        for sk in e_list:
            inputs.remove(sk)

客户端：
import socket

obj = socket.socket()

obj.connect(('127.0.0.1',8001))

while True:
    inp = input("Please(q\退出):\n>>>")
    obj.sendall(bytes(inp,encoding="utf-8"))
    if inp == "q":
        break
    ret = str(obj.recv(1024),encoding="utf-8")
    print(ret)

import  socketserver

class Myserver(socketserver.BaseRequestHandler):

    def handle(self):

        conn = self.request
        conn.sendall(bytes("你好，我是机器人",encoding="utf-8"))
        while True:
            ret_bytes = conn.recv(1024)
            ret_str = str(ret_bytes,encoding="utf-8")
            if ret_str == "q":
                break
            conn.sendall(bytes(ret_str+"你好我好大家好",encoding="utf-8"))

if __name__ == "__main__":
    server = socketserver.ThreadingTCPServer(("127.0.0.1",8080),Myserver)
    server.serve_forever()

import socket

obj = socket.socket()

obj.connect(("127.0.0.1",8080))

ret_bytes = obj.recv(1024)
ret_str = str(ret_bytes,encoding="utf-8")
print(ret_str)

while True:
    inp = input("你好请问您有什么问题？ \n >>>")
    if inp == "q":
        obj.sendall(bytes(inp,encoding="utf-8"))
        break
    else:
        obj.sendall(bytes(inp, encoding="utf-8"))
        ret_bytes = obj.recv(1024)
        ret_str = str(ret_bytes,encoding="utf-8")
        print(ret_str)

class BaseServer:

    """Base class for server classes.

    Methods for the caller:

    - __init__(server_address, RequestHandlerClass)
    - serve_forever(poll_interval=0.5)
    - shutdown()
    - handle_request()  # if you do not use serve_forever()
    - fileno() -> int   # for select()

    Methods that may be overridden:

    - server_bind()
    - server_activate()
    - get_request() -> request, client_address
    - handle_timeout()
    - verify_request(request, client_address)
    - server_close()
    - process_request(request, client_address)
    - shutdown_request(request)
    - close_request(request)
    - handle_error()

    Methods for derived classes:

    - finish_request(request, client_address)

    Class variables that may be overridden by derived classes or
    instances:

    - timeout
    - address_family
    - socket_type
    - allow_reuse_address

    Instance variables:

    - RequestHandlerClass
    - socket

    """

    timeout = None

    def __init__(self, server_address, RequestHandlerClass):
        """Constructor.  May be extended, do not override."""
        self.server_address = server_address
        self.RequestHandlerClass = RequestHandlerClass
        self.__is_shut_down = threading.Event()
        self.__shutdown_request = False

    def server_activate(self):
        """Called by constructor to activate the server.

        May be overridden.

        """
        pass

    def serve_forever(self, poll_interval=0.5):
        """Handle one request at a time until shutdown.

        Polls for shutdown every poll_interval seconds. Ignores
        self.timeout. If you need to do periodic tasks, do them in
        another thread.
        """
        self.__is_shut_down.clear()
        try:
            while not self.__shutdown_request:
                # XXX: Consider using another file descriptor or
                # connecting to the socket to wake this up instead of
                # polling. Polling reduces our responsiveness to a
                # shutdown request and wastes cpu at all other times.
                r, w, e = _eintr_retry(select.select, [self], [], [],
                                       poll_interval)
                if self in r:
                    self._handle_request_noblock()
        finally:
            self.__shutdown_request = False
            self.__is_shut_down.set()

    def shutdown(self):
        """Stops the serve_forever loop.

        Blocks until the loop has finished. This must be called while
        serve_forever() is running in another thread, or it will
        deadlock.
        """
        self.__shutdown_request = True
        self.__is_shut_down.wait()

    # The distinction between handling, getting, processing and
    # finishing a request is fairly arbitrary.  Remember:
    #
    # - handle_request() is the top-level call.  It calls
    #   select, get_request(), verify_request() and process_request()
    # - get_request() is different for stream or datagram sockets
    # - process_request() is the place that may fork a new process
    #   or create a new thread to finish the request
    # - finish_request() instantiates the request handler class;
    #   this constructor will handle the request all by itself

    def handle_request(self):
        """Handle one request, possibly blocking.

        Respects self.timeout.
        """
        # Support people who used socket.settimeout() to escape
        # handle_request before self.timeout was available.
        timeout = self.socket.gettimeout()
        if timeout is None:
            timeout = self.timeout
        elif self.timeout is not None:
            timeout = min(timeout, self.timeout)
        fd_sets = _eintr_retry(select.select, [self], [], [], timeout)
        if not fd_sets[0]:
            self.handle_timeout()
            return
        self._handle_request_noblock()

    def _handle_request_noblock(self):
        """Handle one request, without blocking.

        I assume that select.select has returned that the socket is
        readable before this function was called, so there should be
        no risk of blocking in get_request().
        """
        try:
            request, client_address = self.get_request()
        except socket.error:
            return
        if self.verify_request(request, client_address):
            try:
                self.process_request(request, client_address)
            except:
                self.handle_error(request, client_address)
                self.shutdown_request(request)

    def handle_timeout(self):
        """Called if no new request arrives within self.timeout.

        Overridden by ForkingMixIn.
        """
        pass

    def verify_request(self, request, client_address):
        """Verify the request.  May be overridden.

        Return True if we should proceed with this request.

        """
        return True

    def process_request(self, request, client_address):
        """Call finish_request.

        Overridden by ForkingMixIn and ThreadingMixIn.

        """
        self.finish_request(request, client_address)
        self.shutdown_request(request)

    def server_close(self):
        """Called to clean-up the server.

        May be overridden.

        """
        pass

    def finish_request(self, request, client_address):
        """Finish one request by instantiating RequestHandlerClass."""
        self.RequestHandlerClass(request, client_address, self)

    def shutdown_request(self, request):
        """Called to shutdown and close an individual request."""
        self.close_request(request)

    def close_request(self, request):
        """Called to clean up an individual request."""
        pass

    def handle_error(self, request, client_address):
        """Handle an error gracefully.  May be overridden.

        The default is to print a traceback and continue.

        """
        print '-'*40
        print 'Exception happened during processing of request from',
        print client_address
        import traceback
        traceback.print_exc() # XXX But this goes to stderr!
        print '-'*40

class TCPServer(BaseServer):

    """Base class for various socket-based server classes.

    Defaults to synchronous IP stream (i.e., TCP).

    Methods for the caller:

    - __init__(server_address, RequestHandlerClass, bind_and_activate=True)
    - serve_forever(poll_interval=0.5)
    - shutdown()
    - handle_request()  # if you don't use serve_forever()
    - fileno() -> int   # for select()

    Methods that may be overridden:

    - server_bind()
    - server_activate()
    - get_request() -> request, client_address
    - handle_timeout()
    - verify_request(request, client_address)
    - process_request(request, client_address)
    - shutdown_request(request)
    - close_request(request)
    - handle_error()

    Methods for derived classes:

    - finish_request(request, client_address)

    Class variables that may be overridden by derived classes or
    instances:

    - timeout
    - address_family
    - socket_type
    - request_queue_size (only for stream sockets)
    - allow_reuse_address

    Instance variables:

    - server_address
    - RequestHandlerClass
    - socket

    """

    address_family = socket.AF_INET

    socket_type = socket.SOCK_STREAM

    request_queue_size = 5

    allow_reuse_address = False

    def __init__(self, server_address, RequestHandlerClass, bind_and_activate=True):
        """Constructor.  May be extended, do not override."""
        BaseServer.__init__(self, server_address, RequestHandlerClass)
        self.socket = socket.socket(self.address_family,
                                    self.socket_type)
        if bind_and_activate:
            try:
                self.server_bind()
                self.server_activate()
            except:
                self.server_close()
                raise

    def server_bind(self):
        """Called by constructor to bind the socket.

        May be overridden.

        """
        if self.allow_reuse_address:
            self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
        self.socket.bind(self.server_address)
        self.server_address = self.socket.getsockname()

    def server_activate(self):
        """Called by constructor to activate the server.

        May be overridden.

        """
        self.socket.listen(self.request_queue_size)

    def server_close(self):
        """Called to clean-up the server.

        May be overridden.

        """
        self.socket.close()

    def fileno(self):
        """Return socket file number.

        Interface required by select().

        """
        return self.socket.fileno()

    def get_request(self):
        """Get the request and client address from the socket.

        May be overridden.

        """
        return self.socket.accept()

    def shutdown_request(self, request):
        """Called to shutdown and close an individual request."""
        try:
            #explicitly shutdown.  socket.close() merely releases
            #the socket and waits for GC to perform the actual close.
            request.shutdown(socket.SHUT_WR)
        except socket.error:
            pass #some platforms may raise ENOTCONN here
        self.close_request(request)

    def close_request(self, request):
        """Called to clean up an individual request."""
        request.close()

class ThreadingMixIn:
    """Mix-in class to handle each request in a new thread."""

    # Decides how threads will act upon termination of the
    # main process
    daemon_threads = False

    def process_request_thread(self, request, client_address):
        """Same as in BaseServer but as a thread.

        In addition, exception handling is done here.

        """
        try:
            self.finish_request(request, client_address)
            self.shutdown_request(request)
        except:
            self.handle_error(request, client_address)
            self.shutdown_request(request)

    def process_request(self, request, client_address):
        """Start a new thread to process the request."""
        t = threading.Thread(target = self.process_request_thread,
                             args = (request, client_address))
        t.daemon = self.daemon_threads
        t.start()

class BaseRequestHandler:

    """Base class for request handler classes.

    This class is instantiated for each request to be handled.  The
    constructor sets the instance variables request, client_address
    and server, and then calls the handle() method.  To implement a
    specific service, all you need to do is to derive a class which
    defines a handle() method.

    The handle() method can find the request as self.request, the
    client address as self.client_address, and the server (in case it
    needs access to per-server information) as self.server.  Since a
    separate instance is created for each request, the handle() method
    can define arbitrary other instance variariables.

    """

    def __init__(self, request, client_address, server):
        self.request = request
        self.client_address = client_address
        self.server = server
        self.setup()
        try:
            self.handle()
        finally:
            self.finish()

    def setup(self):
        pass

    def handle(self):
        pass

    def finish(self):
        pass