class_docstr: A Connection class implemented with Fiber socket.
  
  It takes a (sock_type, dest_addr) tuple as input, creates a new connection
  which can send and recv Python objects. This ZConnection class can be
  serialized by pickle and then send to another remote process. Fiber socket
  will be reconnected after unpickle.
  
  :param handle: a (sock_type, dest_addr) tuple.
      `sock_type` should be a Fiber socket type. `dest_addr` should be in
      format like "tcp://127.0.0.1:9000".
  
  > note: ZConnection's fileno method returns a Fiber socket.
code: def __del__(self):
      # __del__ is not reliable, we use atexit to clean up things
      return
  
imports: import logging
  import multiprocessing.connection
  import multiprocessing.reduction
  from multiprocessing.util import register_after_fork
  import atexit
  from fiber.process import current_process
  from fiber.backend import get_backend
  from fiber.socket import Socket, ProcessDevice
label_desc: Use image node_id 4 for calling the ZConnection obj's underlying member method code with example usage: obj.__del__() without return types