code: def to_fastq_apipe_cl(sdf_file, start=None, end=None):
      
      cmd = ["rtg", "sdf2fastq", "--no-gzip", "-o", "-"]
      if start is not None:
          cmd += ["--start-id=%s" % start]
      if end is not None:
          cmd += ["--end-id=%s" % end]
      if is_paired(sdf_file):
          out = []
          for ext in ["left", "right"]:
              out.append("<(%s)" % _rtg_cmd(cmd + ["-i", os.path.join(sdf_file, ext)]))
          return out
      else:
          cmd += ["-i", sdf_file]
          return ["<(%s)" % _rtg_cmd(cmd), None]
docs: Return a command lines to provide streaming fastq input.
  
      For paired end, returns a forward and reverse command line. For
      single end returns a single command line and None for the pair.