code: def fstat(self, file_des):
          
          # stat should return the tuple representing return value of os.stat
          file_object = self.filesystem.get_open_file(file_des).get_object()
          return file_object.stat_result.copy()
docs: Return the os.stat-like tuple for the FakeFile object of file_des.
  
          Args:
              file_des: The file descriptor of filesystem object to retrieve.
  
          Returns:
              The FakeStatResult object corresponding to entry_path.
  
          Raises:
              OSError: if the filesystem object doesn't exist.