Ultralytics Code Refactor https://ultralytics.com/actions (#13152)

Refactor code for speed and clarity

segment/train.py

@@ -216,6 +216,7 @@ def train(hyp, opt, device, callbacks):
     else:
 
         def lf(x):
+            """Linear learning rate scheduler decreasing from 1 to hyp['lrf'] over 'epochs'."""
             return (1 - x / epochs) * (1.0 - hyp["lrf"]) + hyp["lrf"]  # linear
 
     scheduler = lr_scheduler.LambdaLR(optimizer, lr_lambda=lf)  # plot_lr_scheduler(optimizer, scheduler, epochs)

segment/val.py

@@ -91,6 +91,7 @@ def save_one_json(predn, jdict, path, class_map, pred_masks):
     from pycocotools.mask import encode
 
     def single_encode(x):
+        """Encodes binary mask arrays into RLE (Run-Length Encoding) format for JSON serialization."""
         rle = encode(np.asarray(x[:, :, None], order="F", dtype="uint8"))[0]
         rle["counts"] = rle["counts"].decode("utf-8")
         return rle