code: def parseFASTACommandLineOptions(args):
      
      # Set default FASTA type.
      if not (args.fasta or args.fastq or args.fasta_ss):
          args.fasta = True
  
      readClass = readClassNameToClass[args.readClass]
  
      if args.fasta:
          from dark.fasta import FastaReads
          return FastaReads(args.fastaFile, readClass=readClass)
      elif args.fastq:
          from dark.fastq import FastqReads
          return FastqReads(args.fastaFile, readClass=readClass)
      else:
          from dark.fasta_ss import SSFastaReads
          return SSFastaReads(args.fastaFile, readClass=readClass)
docs: Examine parsed command-line options and return a Reads instance.
  
      @param args: An argparse namespace, as returned by the argparse
          C{parse_args} function.
      @return: A C{Reads} subclass instance, depending on the type of FASTA file
          given.