docs: def main():
      """A simple command-line interface for :py:func:`run_simple`."""
  
      # in contrast to argparse, this works at least under Python < 2.7
      import optparse
      from .utils import import_string
  
      parser = optparse.OptionParser(usage="Usage: %prog [options] app_module:app_object")
      parser.add_option(
          "-b",
          "--bind",
          dest="address",
          help="The hostname:port the app should listen on.",
      )
      parser.add_option(
          "-d",
          "--debug",
          dest="use_debugger",
          action="store_true",
          default=False,
          help="Use Werkzeug's debugger.",
      )
      parser.add_option(
          "-r",
          "--reload",
          dest="use_reloader",
          action="store_true",
          default=False,
          help="Reload Python process if modules change.",
      )
      options, args = parser.parse_args()
  
      hostname, port = None, None
      if options.address:
          address = options.address.split(":")
          hostname = address[0]
          if len(address) > 1:
              port = address[1]
  
      if len(args) != 1:
          sys.stdout.write("No application supplied, or too much. See --help\n")
          sys.exit(1)
      app = import_string(args[0])
  
      run_simple(
          hostname=(hostname or "127.0.0.1"),
          port=int(port or 5000),
          application=app,
          use_reloader=options.use_reloader,
          use_debugger=options.use_debugger,
      )