"パーフェクトpython"を見て、Echoアプリケーションを作っていましたが、「python3 client.py」と実行すると、以下のエラーが発生します。どういう意味でしょうか？もちろん、server側のプログラムも立ち上げています。
なお、client側とserver側のコードも示しています。（教材に書いているコードそのままなんですけど。。。）
　解決策も教えていただけませんでしょうか？

【エラー内容】

Traceback (most recent call last):
  File "client.py", line 76, in <module>
    main()
  File "client.py", line 68, in main
    root.after(200, functools.partial(idle_task, root))
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/tkinter/__init__.py", line 752, in after
    callit.__name__ = func.__name__
AttributeError: 'functools.partial' object has no attribute '__name__'

client側コード

# -*- coding::utf-8 -*-
import tkinter
import asyncore
import functools
import sys
class EchoView(tkinter.Frame):
    """ Echo User Interface """
    def __init__(self, master):
        super(EchoView, self).__init__(master)
        self.listcontainer = tkinter.Frame(self)
        self.listbox = tkinter.Listbox(self.listcontainer)
        self.yscroll = tkinter.Scrollbar(self.listcontainer)
        self.listbox.pack(side=tkinter.LEFT, expand=True, fill=tkinter.BOTH)
        self.yscroll.pack(side=tkinter.LEFT, expand=True, fill=tkinter.Y)
        self.listcontainer.pack(expand=True, fill=tkinter.BOTH)
        self.entry = tkinter.Entry(self)
        self.entry.pack(side=tkinter.BOTTOM, expand=True, fill=tkinter.X)
    def get_submit_messegae(self):
        data = self.entry.get()
        self.entry.delete(0, tkinter.END)
        return data
    def show_message(self, message):
        self.listbox.insert(tkinter.END, message)
        self.listbox.see(tkinter.END)
class EchoClient(asyncore.dispatcher_with_send):
    def __init__(self, view):
        super(EchoClient, self).__init__()
        self.create_socket()
        self.buffers = []
        self.view = view
        self.bind_all()
    def bind_all(self):
        self.view.entry.bind('<Return>', self.on_submit)
    def on_submit(self, event):
        message = self.view.get_submit_messegae()
        self.buffers.append(message.encode('utf-8'))
    def handle_write(self):
        if not self.buffers:
            return
        buffer, self.buffers = self.buffers[0],self.buffers[1:]
        self.send(buffer)
    def writable(self):
        return self.buffers
    def handle_read(self):
        message = self.recv(8192)
        self.view.show_message(message.decode('utf-8'))
def idle_task(root):
    try:
        asyncore.loop(count=1, timeout=1)
    finally:
        root.after(200, functools.partial(idle_task, root))
def main():
        root = tkinter.Tk()
        root.after(200, functools.partial(idle_task, root))
        view = EchoView(root)
        view.pack(expand=True, fill=tkinter.BOTH)
        client = EchoClient(view)
        client.connect(('localhost', 8080))
        root.mainloop()
if __name__ == '__main__':
        main()

server側コード

import asyncore
class EchoHandler(asyncore.dispatcher_with_send):
    def __init__(self, socket, parent):
        super(EchoHandler, self).__init__(socket)
        self.parent = parent
    def handle_read(self):
        data = self.recv(8192)
        if data:
            self.parent.send(data)
class EchoServer(asyncore.dispatcher):
    def __init__(self, host, port):
        asyncore.dispatcher.__init__(self)
        self.handlers = []
        self.create_socket()
        self.set_reuse_addr()
        self.bind((host, port))
        self.listen(5)
    def handle_accepted(self, sock, addr):
        print('Incoming connection from %s' % repr(addr))
        handler = EchoHandler(sock)
        self.handlers.append(handler)
    def send(self, data):
        for handler in self.handlers:
            handler.send(data)
server = EchoServer('localhost', 8080)
syncore.loop()

※lambda関数を使用した際のエラーメッセージ

Incoming connection from ('127.0.0.1', 51076)
error: uncaptured python exception, closing channel
<main.EchoServer listening localhost:8080 at 0x107e18f28> (:init() missing 1 required positional argument: 'parent'
[/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/asyncore.py|read|83]
[/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/asyncore.p
y|handle_read_event|416]
[/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/asyncore.p
y|handle_accept|493] [server.py|handle_accepted|27])