docs: def _write_multiplicons(self, filename):
          """ Write multiplicons to file.
  
              - filename, (str) location of output file
          """
          # Column headers
          mhead = '\t'.join(['id', 'genome_x', 'list_x', 'parent', 'genome_y',
                             'list_y', 'level', 'number_of_anchorpoints',
                             'profile_length', 'begin_x', 'end_x', 'begin_y',
                             'end_y', 'is_redundant'])
          with open(filename, 'w') as fhandle:
              fhandle.write(mhead + '\n')
              for mrow in self.multiplicons:
                  fhandle.write('\t'.join([str(e) for e in mrow]) + '\n')