code: def map_to_array(pairs):
      
      if pairs:
          pairs = [TuidMap(*p) for p in pairs]
          max_line = max(p.line for p in pairs)
          tuids = [None] * max_line
          for p in pairs:
              if p.line:  # line==0 IS A PLACEHOLDER FOR FILES THAT DO NOT EXIST
                  tuids[p.line-1] = p.tuid
          return tuids
      else:
          return None
docs: MAP THE (tuid, line) PAIRS TO A SINGLE ARRAY OF TUIDS
      :param pairs:
      :return: