new_contents: """Initialize garage.spiders."""
  
  __all__ = [
      'SPIDER',
      'SPIDER_PARSER',
      'init'
  ]
  
  from startup import startup
  
  import garage.spiders
  from garage.functools import run_once
  from garage.spiders import Spider
  
  from garage.startups import ARGS, PARSE, PARSER
  from garage.startups import components
  from garage.startups.http import CLIENT
  
  
  SPIDER = __name__ + ':spider'
  SPIDER_PARSER = __name__ + ':spider_parser'
  
  
  NUM_SPIDERS = 8
  
  
  def add_arguments(parser: PARSER) -> PARSE:
      group = parser.add_argument_group(garage.spiders.__name__)
      group.add_argument(
          '--num-spiders', default=NUM_SPIDERS, type=int,
          help="""set number of spiders (default to %(default)s)""")
  
  
  def make_spider(args: ARGS, parser: SPIDER_PARSER, client: CLIENT) -> SPIDER:
      return Spider(parser=parser, num_spiders=args.num_spiders, client=client)
  
  
  @run_once
  def init():
      startup(add_arguments)
      components.startup(make_spider)
  
subject: Add startups.spiders