code: def separate_tour_and_o(row):
      
      tour = []
      tour_o = []
      for contig in row.split():
          if contig[-1] in ('+', '-', '?'):
              tour.append(contig[:-1])
              tour_o.append(contig[-1])
          else:  # Unoriented
              tour.append(contig)
              tour_o.append('?')
      return tour, tour_o
docs: The tour line typically contains contig list like:
      tig00044568+ tig00045748- tig00071055- tig00015093- tig00030900-
  
      This function separates the names from the orientations.