Asyncio code is totally sequential!

[mostafaGwely]

i've added this code
if(url == "https://dl.dropboxusercontent.com/s/2fu69d8lfesbhru/pexels-photo-48603.jpeg"):
print("waiting for 10 seconds")
await asyncio.sleep(10)

and as you can see: the downloading process is totally sequential, the asyncio is meant to switch between the dowloads if a url is taking too long to be downloaded, however this is not the case.
this is the output
 
downloading https://dl.dropboxusercontent.com/s/2fu69d8lfesbhru/pexels-photo-48603.jpeg
waiting for 10 seconds
finished downloading https://dl.dropboxusercontent.com/s/2fu69d8lfesbhru/pexels-photo-48603.jpeg
downloading https://dl.dropboxusercontent.com/s/zch88m6sb8a7bm1/pexels-photo-134392.jpeg
finished downloading https://dl.dropboxusercontent.com/s/zch88m6sb8a7bm1/pexels-photo-134392.jpeg
downloading https://dl.dropboxusercontent.com/s/lsr6dxw5m2ep5qt/pexels-photo-135130.jpeg
finished downloading https://dl.dropboxusercontent.com/s/lsr6dxw5m2ep5qt/pexels-photo-135130.jpeg
downloading https://dl.dropboxusercontent.com/s/6xinfm0lcnbirb9/pexels-photo-167300.jpeg
finished downloading https://dl.dropboxusercontent.com/s/6xinfm0lcnbirb9/pexels-photo-167300.jpeg
downloading https://dl.dropboxusercontent.com/s/2dp2hli32h9p0y6/pexels-photo-167921.jpeg
finished downloading https://dl.dropboxusercontent.com/s/2dp2hli32h9p0y6/pexels-photo-167921.jpeg
downloading https://dl.dropboxusercontent.com/s/fjb1m3grcrceqo2/pexels-photo-173125.jpeg
finished downloading https://dl.dropboxusercontent.com/s/fjb1m3grcrceqo2/pexels-photo-173125.jpeg
downloading https://dl.dropboxusercontent.com/s/56u8p4oplagc4bp/pexels-photo-185934.jpeg
finished downloading https://dl.dropboxusercontent.com/s/56u8p4oplagc4bp/pexels-photo-185934.jpeg
downloading https://dl.dropboxusercontent.com/s/2s1x7wz4sdvxssr/pexels-photo-192454.jpeg

[mostafaGwely]

import time
import os
import logging
from urllib.parse import urlparse
from urllib.request import urlretrieve
from queue import Queue
from threading import Thread, Lock
import multiprocessing
import asyncio
import aiohttp
import aiofiles

import PIL
from PIL import Image

FORMAT = "[%(threadName)s, %(asctime)s, %(levelname)s] %(message)s"
logging.basicConfig(filename='logfile.log', level=logging.DEBUG, format=FORMAT)

class ThumbnailMakerService(object):
def init(self, home_dir='.'):
self.home_dir = home_dir
self.input_dir = self.home_dir + os.path.sep + 'incoming'
self.output_dir = self.home_dir + os.path.sep + 'outgoing'
self.img_queue = multiprocessing.JoinableQueue()
self.dl_size = 0
self.resized_size = multiprocessing.Value('i', 0)

async def download_image_coro(self, session, url):
    img_filename = urlparse(url).path.split('/')[-1]
    img_filepath = self.input_dir + os.path.sep + img_filename

    async with session.get(url) as response:
        async with aiofiles.open(img_filepath, mode='wb') as f:
            content = await response.content.read()
            await f.write(content)

    if(url == "https://dl.dropboxusercontent.com/s/2fu69d8lfesbhru/pexels-photo-48603.jpeg"):
        print("waiting for 10 seconds")
        await asyncio.sleep(10)

    self.dl_size += os.path.getsize(img_filepath)
    self.img_queue.put(img_filename)
    print("f " + url)

async def download_images_coro(self, img_url_list):
    async with aiohttp.ClientSession() as session:
        for url in img_url_list:
            print("downloading" + " " + url)
            await self.download_image_coro(session, url)

def download_images(self, img_url_list):
    # validate inputs
    if not img_url_list:
        return
    os.makedirs(self.input_dir, exist_ok=True)

    logging.info("beginning image downloads")
    start = time.perf_counter()

    loop = asyncio.get_event_loop()
    try:
        loop.run_until_complete(self.download_images_coro(img_url_list))
    finally:
        loop.close()

    end = time.perf_counter()
    logging.info("downloaded {} images in {} seconds".format(len(img_url_list), end - start))

def perform_resizing(self):
    # validate inputs
    os.makedirs(self.output_dir, exist_ok=True)

    logging.info("beginning image resizing")
    target_sizes = [32, 64, 200]

    while True:
        filename = self.img_queue.get()
        if filename:
            logging.info("resizing image {}".format(filename))
            orig_img = Image.open(self.input_dir + os.path.sep + filename)
            for basewidth in target_sizes:
                img = orig_img
                # calculate target height of the resized image to maintain the aspect ratio
                wpercent = (basewidth / float(img.size[0]))
                hsize = int((float(img.size[1]) * float(wpercent)))
                # perform resizing
                img = img.resize((basewidth, hsize), PIL.Image.LANCZOS)

                # save the resized image to the output dir with a modified file name
                new_filename = os.path.splitext(filename)[0] + \
                    '_' + str(basewidth) + os.path.splitext(filename)[1]
                out_filepath = self.output_dir + os.path.sep + new_filename
                img.save(out_filepath)

                with self.resized_size.get_lock():
                    self.resized_size.value += os.path.getsize(out_filepath)

            os.remove(self.input_dir + os.path.sep + filename)
            logging.info("done resizing image {}".format(filename))
            self.img_queue.task_done()
        else:
            self.img_queue.task_done()
            break

def make_thumbnails(self, img_url_list):
    logging.info("START make_thumbnails")
    start = time.perf_counter()


    self.download_images(img_url_list)



    end = time.perf_counter()
    logging.info("END make_thumbnails in {} seconds".format(end - start))
    logging.info("Initial size of downloads: [{}]  Final size of images: [{}]".format(self.dl_size, self.resized_size.value))

IMG_URLS =
['https://dl.dropboxusercontent.com/s/2fu69d8lfesbhru/pexels-photo-48603.jpeg',
'https://dl.dropboxusercontent.com/s/zch88m6sb8a7bm1/pexels-photo-134392.jpeg',
'https://dl.dropboxusercontent.com/s/lsr6dxw5m2ep5qt/pexels-photo-135130.jpeg',
'https://dl.dropboxusercontent.com/s/6xinfm0lcnbirb9/pexels-photo-167300.jpeg',
'https://dl.dropboxusercontent.com/s/2dp2hli32h9p0y6/pexels-photo-167921.jpeg',
'https://dl.dropboxusercontent.com/s/fjb1m3grcrceqo2/pexels-photo-173125.jpeg',
'https://dl.dropboxusercontent.com/s/56u8p4oplagc4bp/pexels-photo-185934.jpeg',
'https://dl.dropboxusercontent.com/s/2s1x7wz4sdvxssr/pexels-photo-192454.jpeg',
'https://dl.dropboxusercontent.com/s/1gjphqnllzm10hh/pexels-photo-193038.jpeg',
'https://dl.dropboxusercontent.com/s/pcjz40c8pxpy057/pexels-photo-193043.jpeg',
'https://dl.dropboxusercontent.com/s/hokdfk7y8zmwe96/pexels-photo-207962.jpeg',
'https://dl.dropboxusercontent.com/s/k2tk2co7r18juy7/pexels-photo-247917.jpeg',
'https://dl.dropboxusercontent.com/s/m4xjekvqk4rksbx/pexels-photo-247932.jpeg',
'https://dl.dropboxusercontent.com/s/znmswtwhcdbpc10/pexels-photo-265186.jpeg',
'https://dl.dropboxusercontent.com/s/jgb6n4esquhh4gu/pexels-photo-302899.jpeg',
'https://dl.dropboxusercontent.com/s/rjuggi2ubc1b3bk/pexels-photo-317156.jpeg',
'https://dl.dropboxusercontent.com/s/cpaog2nwplilrz9/pexels-photo-317383.jpeg',
'https://dl.dropboxusercontent.com/s/16x2b6ruk18gji5/pexels-photo-320007.jpeg',
'https://dl.dropboxusercontent.com/s/xqzqzjkcwl52en0/pexels-photo-322207.jpeg',
'https://dl.dropboxusercontent.com/s/frclthpd7t8exma/pexels-photo-323503.jpeg',
'https://dl.dropboxusercontent.com/s/7ixez07vnc3jeyg/pexels-photo-324030.jpeg',
'https://dl.dropboxusercontent.com/s/1xlgrfy861nyhox/pexels-photo-324655.jpeg',
'https://dl.dropboxusercontent.com/s/v1b03d940lop05d/pexels-photo-324658.jpeg',
'https://dl.dropboxusercontent.com/s/ehrm5clkucbhvi4/pexels-photo-325520.jpeg',
'https://dl.dropboxusercontent.com/s/l7ga4ea98hfl49b/pexels-photo-333529.jpeg',
'https://dl.dropboxusercontent.com/s/rleff9tx000k19j/pexels-photo-341520.jpeg'
]

tn_maker = ThumbnailMakerService()
tn_maker.make_thumbnails(IMG_URLS)