code: def format_pair_list(self, key, pair_list, level):
          
  
          lines = [self.add_start_line(key, level)]
  
          list_spacer = self.spacer * (level + 2)
          pairs = ["{}{} {}".format(list_spacer, p[0], p[1]) for p in pair_list]
          lines += pairs
  
          lines.append(self.add_end_line(level, 1, key))
  
          return lines
docs: Process lists of pairs (e.g. PATTERN block)