Shorten module paths with new 'nn' dir (#96)

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

ultralytics/yolo/v8/detect/train.py

@@ -2,6 +2,7 @@ import hydra
 import torch
 import torch.nn as nn
 
+from ultralytics.nn.tasks import DetectionModel
 from ultralytics.yolo import v8
 from ultralytics.yolo.data import build_dataloader
 from ultralytics.yolo.data.dataloaders.v5loader import create_dataloader
@@ -9,7 +10,6 @@ from ultralytics.yolo.engine.trainer import DEFAULT_CONFIG, BaseTrainer
 from ultralytics.yolo.utils import colorstr
 from ultralytics.yolo.utils.loss import BboxLoss
 from ultralytics.yolo.utils.metrics import smooth_BCE
-from ultralytics.yolo.utils.modeling.tasks import DetectionModel
 from ultralytics.yolo.utils.ops import xywh2xyxy
 from ultralytics.yolo.utils.plotting import plot_images, plot_results
 from ultralytics.yolo.utils.tal import TaskAlignedAssigner, dist2bbox, make_anchors