app.py

from flask import Flask
import grequests
import time
import threading
class Unbuffered(object):
   def __init__(self, stream):
       self.stream = stream
   def write(self, data):
       self.stream.write(data)
       self.stream.flush()
   def writelines(self, datas):
       self.stream.writelines(datas)
       self.stream.flush()
   def __getattr__(self, attr):
       return getattr(self.stream, attr)
import sys
sys.stdout = Unbuffered(sys.stdout)

def myfunc():
  num = 1000
  url = "https://storage.nts.org.pk/upload/565510/userpic/565510_"
  thislist = ["https://storage.nts.org.pk/upload/565510/userpic/565510_1000.jpg"]
  while True:
      num=num+1
      new_url = url+str(num)+".jpg"

      thislist.append(new_url)
      if(num==10000):

          break
  print("list completed")
  # start_time = time.time()

  urls = thislist
  rs = (grequests.head(u) for u in urls)
  x=1000
  for response in grequests.map(rs):
    x=x+1
    # print(response.status_code, response.elapsed.total_seconds())
    if(response.status_code==200):
      print("Got it at "+str(x))


app = Flask(__name__)


@app.route('/')
def hello_world():
  
  return 'Hello World'
@app.route('/start')
def started():
  t1 = threading.Thread(target=myfunc)
  t1.start()
  return 'Started'

if __name__ == '__main__':


	app.run()