old_contents: #!/usr/bin/env python
  
  from circuits.net.sockets import TCPServer
  
  class EchoServer(TCPServer):
  
      def read(self, sock, data):
          self.write(sock, data)
      
  EchoServer(8000).run()
  
new_contents: #!/usr/bin/env python
  
  from circuits.net.sockets import TCPServer, Write
  
  class EchoServer(TCPServer):
  
      def read(self, sock, data):
          self.push(Write(sock, data))
      
  EchoServer(8000).run()
  
subject: Use Write Event in echoserver.py