code: def main():
      from tornado.options import define, options, parse_command_line
  
      define("print_headers", type=bool, default=False)
      define("print_body", type=bool, default=True)
      define("follow_redirects", type=bool, default=True)
      define("validate_cert", type=bool, default=True)
      args = parse_command_line()
      client = HTTPClient()
      for arg in args:
          try:
              response = client.fetch(
                  arg,
                  follow_redirects=options.follow_redirects,
                  validate_cert=options.validate_cert,
              )
          except HTTPError as e:
              if e.response is not None:
                  response = e.response
              else:
                  raise
          if options.print_headers:
              print(response.headers)
          if options.print_body:
              print(native_str(response.body))
      client.close()
  
imports: from __future__ import absolute_import, division, print_function
  import functools
  import time
  import weakref
  from tornado.concurrent import TracebackFuture
  from tornado.escape import utf8, native_str
  from tornado import httputil, stack_context
  from tornado.ioloop import IOLoop
  from tornado.util import Configurable
label_desc: Use image node_id 1 for calling a global function with example usage: main() without return types