code: def __init__(
      self,
      feature_dim: int = 2048,
      num_classes: int = 1000,
      topk: Tuple[int, ...] = (1, 5),
  ) -> None:
      super().__init__()
      self.feature_dim = feature_dim
      self.num_classes = num_classes
      self.topk = topk
  
      self.classification_head = Linear(feature_dim, num_classes)
      self.criterion = CrossEntropyLoss()
  
file_path: lightly/lightly/utils/benchmarking/online_linear_classifier.py
imports: from typing import Dict, Tuple
  from pytorch_lightning import LightningModule
  from torch import Tensor
  from torch.nn import CrossEntropyLoss, Linear
  from lightly.utils.benchmarking.topk import mean_topk_accuracy
label_desc: Use image node_id 1 to create a new OnlineLinearClassifier object from inherited base classes: LightningModule with example: obj = OnlineLinearClassifier(feature_dim, num_classes, topk)