code: def _inner_close(self):
      if self.out_file is not None:
          self.out_file.close()
          self.out_file = None
      if self.in_file is not None:
          self.in_file.close()
          self.in_file = None
  
file_path: nni/nni/tools/trial_tool/file_channel.py
imports: import os
  from .base_channel import BaseChannel
label_desc: Use image node_id 3 for calling the FileChannel obj's underlying member method code with example usage: obj._inner_close() without return types