code: def uclust_cluster_from_sorted_fasta_filepath(
          fasta_filepath,
          uc_save_filepath=None,
          percent_ID=0.97,
          max_accepts=1,
          max_rejects=8,
          stepwords=8,
          word_length=8,
          optimal=False,
          exact=False,
          suppress_sort=False,
          enable_rev_strand_matching=False,
          subject_fasta_filepath=None,
          suppress_new_clusters=False,
          stable_sort=False,
          tmp_dir=gettempdir(),
          HALT_EXEC=False):
      output_filepath = uc_save_filepath
      if not output_filepath:
          _, output_filepath = mkstemp(dir=tmp_dir, prefix='uclust_clusters',
                                       suffix='.uc')
      params = {'--id': percent_ID,
                '--maxaccepts': max_accepts,
                '--maxrejects': max_rejects,
                '--stepwords': stepwords,
                '--w': word_length,
                '--tmpdir': tmp_dir}
      app = Uclust(params,
                   TmpDir=tmp_dir, HALT_EXEC=HALT_EXEC)
      if enable_rev_strand_matching:
          app.Parameters['--rev'].on()
      if optimal:
          app.Parameters['--optimal'].on()
      if exact:
          app.Parameters['--exact'].on()
      if suppress_sort:
          app.Parameters['--usersort'].on()
      if subject_fasta_filepath:
          app.Parameters['--lib'].on(subject_fasta_filepath)
      if suppress_new_clusters:
          app.Parameters['--libonly'].on()
      if stable_sort:
          app.Parameters['--stable_sort'].on()
      app_result = app({'--input': fasta_filepath, '--uc': output_filepath})
      return app_result