一个小聊天室的代码运行总是报错

Python code

# coding=gbk'''Created on 2012-5-22@author: dengjian'''from asyncore import dispatcherfrom asynchat import async_chatimport socket,asyncorePORT= 5005NAME='TestChat'class EndSession(Exception): passclass CommandHandler:    """    类似于标准库cmd.Cmd的简单命令处理程序。    """        def unknown(self,session,cmd):        #'响应未知命令'        session.push('Unknown command: %s\r\n' % cmd)            def handle(self,session,line):        #'处理从给定的会话中接收到的行'        if not line.strip(): return        #分离命令        parts=line.split(' ',1)        cmd=parts[0]        try : line=parts[1].strip()        except IndexError: line=''        #试着查找处理程序：        meth=getattr(self,'do_'+cmd,None)        try:            #假如它是可调用的            meth(session,line)        except TypeError:            # 如果不可以被调用，此段代码响应未知的命令：            self.unknown(session,cmd)            class Room(CommandHandler):    """    包括一个或多个用户（会话）的泛型环境。它负责基本的命令处理和广播。    """    def __init__(self,server):        self.server=server        self.sessions=[]            def add(self,session):        #'一个会话（用户）已进入房间'        self.sessions.append(session)            def remove(self,session):        #'一个会话（用户）已离开房间'        self.sessions.remove(session)            def broadcast(self,line):        #'向房间中的所有会话发送一行'        for session in self.sessions:            session.push(line)                def do_logout(self,session,line):        #'响应logout命令'        raise EndSession    class LoginRoom(Room):    """    为刚刚连接上的用户准备的房间。    """    def add(self,session):        Room.add(self, session)        #当用户进入时，问题他或她：        self.broadcast('welcome to %s\r\n' % self.server.name)            def unknown(self,session,cmd):        #所有未知命令（除了login或者logout外一切）        #会导致一个警告        session.push('Please log in \n Use "login <nick> "\r\n')            def do_login(self,session,line):        name=line.strip()        #确保用户输入了名字        if not name:            session.push('Please enter a name\r\n')        #确保用户名没有被利用：        elif name in self.server.users:            session.push('The name "%s" is taken.\r\n' % name)            session.push('Please try again.\r\n')        else:            #名字没问题，所以存储在会话中，并且            #将用户移动到主聊天室。            session.name=name            session.enter(self.server.main_room)            class ChatRoom(Room):    """    为多用户相互聊天准备的房间    """        def add(self,session):        #告诉所有人有新用户进入        self.broadcast(session.name + 'has entered the room.\r\n')        self.server.users[session.name]=session        Room.add(self.session)            def remove(self,session):        Room.remove(self, session)        #告诉所有人有用户离开：        self.broadcast(session.name + 'has left the room.\r\n')            def do_say(self,session,line):        self.broadcast(session.name + ': ' +line+'\r\n')            def do_look(self,session,line):        #'处理look命令，该命令用于查看谁在房间内'        session.push('The following are in this room:\r\n')        for other in self.sessions:            session.push(other.name + '\r\n')                def do_who(self,session,line):        #'处理who命令，该命令用于查看谁登录了'        session.push('The following are logged in:\r\n')        for name in self.server.users:            session.push(name + '\r\n')            class LogoutRoom(Room):    """    为单用户准备的简单房间，只用于将用户名从服务器移除。    """    def add(self,session):        #当会话（用户）进入要删除的logoutRomm时        try: del self.server.users[session.name]        except KeyError: pass        class ChatSession(async_chat):    """    单会话，负责和单用户通信    """    def __init__(self,server,sock):        async_chat.__init__(self, sock)        self.server=server        self.set_terminator("\r\n")        self.data=[]        self.name=None        #所有的会话都开始于单独的LoginRoom中：        self.enter(LoginRoom(server))            def enter(self,room):        #从当前房间移除自身(self)，并且将自身添加到        #下一个房间        try: cur=self.room        except AttributeError: pass        else: cur.remove(self)        self.room=room        room.add(self)            def collect_incoming_data(self,data):        self.data.append(data)                    def found_terminator(self):        line=''.join(self.data)        self.data=[]        try: self.room.handle(self,line)        except EndSession:            self.handle_close()                def handle_close(self):        async_chat.handle_close(self)        self.enter(LogoutRoom(self.server))        class ChatServer(dispatcher):    """    只有一个房间的聊天服务器。    """    def __init__(self,port,name):        dispatcher.__init__(self)        self.create_socket(socket.AF_INET,socket.SOCK_STREAM)        self.set_reuse_addr()        self.bind(('',port))        self.listen(5)        self.name=name        self.users={}        self.main_room=ChatRoom(self)            def handle_accept(self):        conn, addr=self.accept()        ChatSession(self,conn)        if __name__=='__main__':    s = ChatServer(PORT,NAME)    try: asyncore.loop()    except KeyboardInterrupt: print 
 

刚运行时不会报错，但是输入：login 用户名，就会有以下的错误

Traceback (most recent call last):
File "/home/dengjian/workspace/code24/chatserver.py", line 193, in <module>
try: asyncore.loop()
File "/usr/lib/python2.7/asyncore.py", line 210, in loop
error: uncaptured python exception, closing channel <__main__.ChatSession connected 127.0.0.1:37790 at 0xb707ecec> (<type 'exceptions.AttributeError'>:ChatRoom instance has no attribute 'session' [/usr/lib/python2.7/asyncore.py|read|79] [/usr/lib/python2.7/asyncore.py|handle_read_event|438] [/usr/lib/python2.7/asynchat.py|handle_read|158] [/home/dengjian/workspace/code24/chatserver.py|found_terminator|165] [/home/dengjian/workspace/code24/chatserver.py|handle|37] [/home/dengjian/workspace/code24/chatserver.py|do_login|94] [/home/dengjian/workspace/code24/chatserver.py|enter|156] [/home/dengjian/workspace/code24/chatserver.py|add|105])
poll_fun(timeout, map)
File "/usr/lib/python2.7/asyncore.py", line 151, in poll
read(obj)
File "/usr/lib/python2.7/asyncore.py", line 83, in read
obj.handle_error()
File "/usr/lib/python2.7/asyncore.py", line 495, in handle_error
self.handle_close()
File "/home/dengjian/workspace/code24/chatserver.py", line 171, in handle_close
self.enter(LogoutRoom(self.server))
File "/home/dengjian/workspace/code24/chatserver.py", line 154, in enter
else: cur.remove(self)
File "/home/dengjian/workspace/code24/chatserver.py", line 108, in remove
Room.remove(self, session)
File "/home/dengjian/workspace/code24/chatserver.py", line 56, in remove
self.sessions.remove(session)
ValueError: list.remove(x): x not in list

查了几天了，都没有找到问题，求大牛帮助

[解决办法]

探讨

File "/home/dengjian/workspace/code24/chatserver.py", line 154, in enter
else: cur.remove(self)
File "/home/dengjian/workspace/code24/chatserver.py", line 108, in remove
Room.remove(self, session)
File "/home/dengjian/workspace/code24/chatserver.py", line 56, in remove
self.sessions.remove(session)
ValueError: list.remove(x): x not in list

[解决办法]
呵呵，不好意思，看错啦，刚睡醒...