ultralytics 8.0.81 single-line docstring updates (#2061)

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

ultralytics/yolo/utils/callbacks/base.py

@@ -2,111 +2,144 @@
 """
 Base callbacks
 """
+
 from collections import defaultdict
 from copy import deepcopy
 
-
 # Trainer callbacks ----------------------------------------------------------------------------------------------------
+
+
 def on_pretrain_routine_start(trainer):
+    """Called before the pretraining routine starts."""
     pass
 
 
 def on_pretrain_routine_end(trainer):
+    """Called after the pretraining routine ends."""
     pass
 
 
 def on_train_start(trainer):
+    """Called when the training starts."""
     pass
 
 
 def on_train_epoch_start(trainer):
+    """Called at the start of each training epoch."""
     pass
 
 
 def on_train_batch_start(trainer):
+    """Called at the start of each training batch."""
     pass
 
 
 def optimizer_step(trainer):
+    """Called when the optimizer takes a step."""
     pass
 
 
 def on_before_zero_grad(trainer):
+    """Called before the gradients are set to zero."""
     pass
 
 
 def on_train_batch_end(trainer):
+    """Called at the end of each training batch."""
     pass
 
 
 def on_train_epoch_end(trainer):
+    """Called at the end of each training epoch."""
     pass
 
 
 def on_fit_epoch_end(trainer):
+    """Called at the end of each fit epoch (train + val)."""
     pass
 
 
 def on_model_save(trainer):
+    """Called when the model is saved."""
     pass
 
 
 def on_train_end(trainer):
+    """Called when the training ends."""
     pass
 
 
 def on_params_update(trainer):
+    """Called when the model parameters are updated."""
     pass
 
 
 def teardown(trainer):
+    """Called during the teardown of the training process."""
     pass
 
 
 # Validator callbacks --------------------------------------------------------------------------------------------------
+
+
 def on_val_start(validator):
+    """Called when the validation starts."""
     pass
 
 
 def on_val_batch_start(validator):
+    """Called at the start of each validation batch."""
     pass
 
 
 def on_val_batch_end(validator):
+    """Called at the end of each validation batch."""
     pass
 
 
 def on_val_end(validator):
+    """Called when the validation ends."""
     pass
 
 
 # Predictor callbacks --------------------------------------------------------------------------------------------------
+
+
 def on_predict_start(predictor):
+    """Called when the prediction starts."""
     pass
 
 
 def on_predict_batch_start(predictor):
+    """Called at the start of each prediction batch."""
     pass
 
 
 def on_predict_batch_end(predictor):
+    """Called at the end of each prediction batch."""
     pass
 
 
 def on_predict_postprocess_end(predictor):
+    """Called after the post-processing of the prediction ends."""
     pass
 
 
 def on_predict_end(predictor):
+    """Called when the prediction ends."""
     pass
 
 
 # Exporter callbacks ---------------------------------------------------------------------------------------------------
+
+
 def on_export_start(exporter):
+    """Called when the model export starts."""
     pass
 
 
 def on_export_end(exporter):
+    """Called when the model export ends."""
     pass
 
 
@@ -146,10 +179,23 @@ default_callbacks = {
 
 
 def get_default_callbacks():
+    """
+    Return a copy of the default_callbacks dictionary with lists as default values.
+
+    Returns:
+        (defaultdict): A defaultdict with keys from default_callbacks and empty lists as default values.
+    """
     return defaultdict(list, deepcopy(default_callbacks))
 
 
 def add_integration_callbacks(instance):
+    """
+    Add integration callbacks from various sources to the instance's callbacks.
+
+    Args:
+        instance (Trainer, Predictor, Validator, Exporter): An object with a 'callbacks' attribute that is a dictionary
+            of callback lists.
+    """
     from .clearml import callbacks as clearml_callbacks
     from .comet import callbacks as comet_callbacks
     from .hub import callbacks as hub_callbacks