class BaseServer:
    def process_request(self, request, client_address):
        """Can be Overridden by ForkingMixIn and ThreadingMixIn."""
        pass

class TCPServer(BaseServer):
    def __init__(self, *args, **kwargs):
      # bind the TCP socket to a address and listen to the socket
      # the rest would be handled by the BaseServer
      pass

class ForkingMixIn:
    def process_request(self, request, client_address):
        """Fork a new subprocess to process the request."""
        pass

class ThreadingMixIn:
    def process_request(self, request, client_address):
        """Create a new non-daemonic thread to process the request."""
        pass
      
class ForkingTCPServer(ForkingMixIn, TCPServer):
    pass
  
class ThreadingTCPServer(ThreadingMixIn, TCPServer):
    pass