Publish a CommandFailedEvent to all command listeners.

        :Parameters:
          - `duration`: The command duration as a datetime.timedelta.
          - `failure`: The server reply document or failure description
            document.
          - `command_name`: The command name.
          - `request_id`: The request id for this operation.
          - `connection_id`: The address (host, port) of the server this
            command was sent to.
          - `op_id`: The (optional) operation id for this operation.

def publish_command_failure(self, duration, failure, command_name,
                                request_id, connection_id, op_id=None):
        """Publish a CommandFailedEvent to all command listeners.

        :Parameters:
          - `duration`: The command duration as a datetime.timedelta.
          - `failure`: The server reply document or failure description
            document.
          - `command_name`: The command name.
          - `request_id`: The request id for this operation.
          - `connection_id`: The address (host, port) of the server this
            command was sent to.
          - `op_id`: The (optional) operation id for this operation.
        """
        if op_id is None:
            op_id = request_id
        event = CommandFailedEvent(
            duration, failure, command_name, request_id, connection_id, op_id)
        for subscriber in self.__command_listeners:
            try:
                subscriber.failed(event)
            except Exception:
                _handle_exception()