code: def connection_lost(self, exc):
      self.disconnected = True
      self.proc._pipe_connection_lost(self.fd, exc)
      self.proc = None
  
imports: import collections
  import subprocess
  import warnings
  from .None import protocols
  from .None import transports
  from .log import logger
label_desc: Use image node_id 4 for calling the WriteSubprocessPipeProto obj's underlying member method code with example usage: obj.connection_lost(exc) without return types