          histograms = [cv2.calcHist([img], [0], None, [256], [0, 256]) for img in image_list]
          img_list = list(list(items) for items in zip(filename_list, histograms, scores))
  
          img_list_len = len(img_list)
          for i in tqdm(range(0, img_list_len), desc="Comparing", file=sys.stdout):
              score_total = 0
              for j in range(0, img_list_len):
                  if i == j:
 
</s> remove         img_list = [
            [img,
             cv2.calcHist([read_image(img, raise_error=True)], [0], None, [256], [0, 256]), 0]
            for img in
            tqdm(self.find_images(input_dir), desc="Loading", file=sys.stdout)
        ]
 </s> add         logger.info("Calculating histograms...")
        histograms = [cv2.calcHist([img], [0], None, [256], [0, 256]) for img in image_list]
        img_list = list(list(items) for items in zip(filename_list, histograms, scores)) </s> remove         for i in tqdm(range(0, img_list_len), desc="Sorting", file=sys.stdout):
 </s> add         for i in tqdm(range(0, img_list_len), desc="Comparing", file=sys.stdout):
        logger.info("Comparing histograms...")
          histograms = [cv2.calcHist([img], [0], None, [256], [0, 256]) for img in image_list]
          img_list = list(list(items) for items in zip(filename_list, histograms, scores))
  
        logger.info("Comparing histograms...")
          img_list_len = len(img_list)
          for i in tqdm(range(0, img_list_len), desc="Comparing", file=sys.stdout):
              score_total = 0
              for j in range(0, img_list_len):
                  if i == j:
keep keep add keep keep keep keep keep
 ENHANCEMENT: Sort image multi-threading and code clarity (#912)

* Use multi-threaded loading

* fast reload

* remove landmark stub

* saves

* correct face sort

* pep8 
tools/sort.py