docs: def save(self, path):
          """Saves this catalogue's data to `path`.
  
          :param path: file path to save catalogue data to
          :type path: `str`
  
          """
          writer = csv.writer(open(path, 'w', newline=''), delimiter=' ')
          rows = list(self.items())
          rows.sort(key=lambda x: x[0])
          writer.writerows(rows)