code: def on_train_end(self) -> None:
      activate_requires_grad(self.backbone)
      activate_requires_grad(self.projection_head)
  
imports: import copy
  from typing import List, Tuple, Union
  import torch
  from pytorch_lightning import LightningModule
  from torch import Tensor
  from torch.nn import Identity
  from torch.optim import SGD
  from torch.optim.optimizer import Optimizer
  from torchvision.models import resnet50
  from lightly.loss import DINOLoss
  from lightly.models.modules import DINOProjectionHead
  from lightly.models.utils import activate_requires_grad, deactivate_requires_grad, get_weight_decay_parameters, update_momentum
  from lightly.transforms import DINOTransform
  from lightly.utils.benchmarking import OnlineLinearClassifier
  from lightly.utils.scheduler import CosineWarmupScheduler, cosine_schedule
label_desc: Use image node_id 5 for calling the DINO obj's underlying member method code with example usage: obj.on_train_end() without return types