code: def _inner_receive(self):
      messages = []
      if self.client is not None:
          received = self._event_loop.run_until_complete(
              self.client.recv()
          )
          # receive message is string, to get consistent result, encode it here.
          self.in_cache += received.encode("utf8")
          messages, self.in_cache = self._fetch_message(self.in_cache)
  
      return messages
  
file_path: nni/nni/tools/trial_tool/web_channel.py
imports: import asyncio
  import os
  import websockets
  from .base_channel import BaseChannel
  from .log_utils import LogType, nni_log
label_desc: Use image node_id 5 for calling the WebChannel obj's underlying member method code with example usage: obj._inner_receive() and returns: messages