code: def load_session_from_file(self, username: str, filename: Optional[str] = None) -> None:
          
          if filename is None:
              filename = get_default_session_filename(username)
          with open(filename, 'rb') as sessionfile:
              self.context.load_session_from_file(username, sessionfile)
              self.context.log("Loaded session from %s." % filename)
docs: Internally stores :class:`requests.Session` object loaded from file.
  
          If filename is None, the file with the default session path is loaded.
  
          :raises FileNotFoundError: If the file does not exist.