code: def __add_recent_file(self, fname):
          
          if fname is None:
              return
          if fname in self.recent_files:
              self.recent_files.remove(fname)
          self.recent_files.insert(0, fname)
          if len(self.recent_files) > self.get_option('max_recent_files'):
              self.recent_files.pop(-1)
docs: Add to recent file list