text: #!/usr/bin/env python3
  """ Generate long sequence """
  
  import argparse
  import random
  from typing import NamedTuple, TextIO
  
  
  class Args(NamedTuple):
      """ Command-line arguments """
      seq_len: int
      num_seqs: int
      out_file: TextIO
  
  
  # --------------------------------------------------
  def get_args() -> Args:
      """ Get command-line arguments """
  
      parser = argparse.ArgumentParser(
          description='Generate long sequence',
          formatter_class=argparse.ArgumentDefaultsHelpFormatter)
  
      parser.add_argument('-l',
                          '--len',
                          help='Sequence length',
                          metavar='int',
                          type=int,
                          default=1000000)
  
      parser.add_argument('-n',
                          '--num',
                          help='Number of sequences',
                          metavar='int',
                          type=int,
                          default=100)
  
      parser.add_argument('-o',
                          '--outfile',
                          help='Output file',
                          metavar='FILE',
                          type=argparse.FileType('wt'),
                          default='seq.txt')
  
      args = parser.parse_args()
  
      return Args(args.len, args.num, args.outfile)
  
  
  # --------------------------------------------------
  def main() -> None:
      """ Make a jazz noise here """
  
      args = get_args()
      for _ in range(args.num_seqs):
          print(''.join([random.choice('ACGT') for _ in range(args.seq_len)]),
                file=args.out_file)
      print(f'Done, see "{args.out_file.name}".')
  
  
  # --------------------------------------------------
  if __name__ == '__main__':
      main()
  