title: Share list between process in python server
body: <p>I have simple <strong>UDPServer</strong>, which works with <strong>multiprocessing</strong>. </p>
  
  <p>I want to create a list, that contains information about all clients. </p>
  
  <p>I use <strong>Manager</strong>, but I don't understand, how to append information in list - I need transfer Manager`s object to handle, but how? My way with new attribute does not work.</p>
  
  <pre><code>import multiprocessing
  from socketserver import UDPServer, ForkingMixIn, DatagramRequestHandler
  from socket import socket, AF_INET, SOCK_DGRAM
  from settings import host, port, number_of_connections
  
  class ChatHandler(DatagramRequestHandler):
  
      def handle(self):
          cur_process = multiprocessing.current_process()
          data = self.request[0].strip()
          socket = self.request[1]
          ChatHandler.clients.append(self.client_address) # error here
          print(ChatHandler.clients)
  
  
  class ChatServer(ForkingMixIn, UDPServer):
      pass
  
  
  if __name__ == '__main__':
      server = ChatServer((host, port), ChatHandler)
      ChatHandler.clients = multiprocessing.Manager().list()
      server_process = multiprocessing.Process(target=server.serve_forever)
      server_process.daemon = False
      server_process.start()
  </code></pre>
  
  <p>How to fix that? Thanks!</p>
  
  <p><strong>Output:</strong></p>
  
  <pre><code>Exception happened during processing of request from ('127.0.0.1', 55679)
  Traceback (most recent call last):
    File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/multiprocessing/managers.py", line 724, in _callmethod
      conn = self._tls.connection
  AttributeError: 'ForkAwareLocal' object has no attribute 'connection'
  
  During handling of the above exception, another exception occurred:
  
  Traceback (most recent call last):
    File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/socketserver.py", line 584, in process_request
      self.finish_request(request, client_address)
    File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/socketserver.py", line 344, in finish_request
      self.RequestHandlerClass(request, client_address, self)
    File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/socketserver.py", line 665, in __init__
      self.handle()
    File "server.py", line 15, in handle
      ChatHandler.clients.append(self.client_address)
    File "&lt;string&gt;", line 2, in append
    File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/multiprocessing/managers.py", line 728, in _callmethod
      self._connect()
    File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/multiprocessing/managers.py", line 715, in _connect
      conn = self._Client(self._token.address, authkey=self._authkey)
    File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/multiprocessing/connection.py", line 495, in Client
      c = SocketClient(address)
    File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/multiprocessing/connection.py", line 624, in SocketClient
      s.connect(address)
  FileNotFoundError: [Errno 2] No such file or directory
  </code></pre>