import torch import torchvision from torch import nn def create_effnet_b2_model(num_classes: int = 3, seed: int = 42): """ Creates an EfficientNetB2 feature extractor model and transforms. Args: num_classes (int, optional): number of classes in the classifier head. Defaults to 3. seed (int, optional): random seed value. Defaults to 42. Returns: model (torch.nn.Module): EffNetB2 feature extractor model. transforms (torchvision.transforms): EffNetB2 image transforms. """ # 1. Setup pretrained weights weights = torchvision.models.EfficientNet_B2_Weights.DEFAULT # 2.Get transforms transforms = weights.transforms() # 3. Cretate the pretrained model model = torchvision.models.efficientnet_b2(weights=weights) # 4. Freeze the base layer for param in model.parameters(): param.requires_grad = False # 5. Update the classifier head to suit our data with reproducibility torch.manual_seed(seed) model.classifier = nn.Sequential( nn.Dropout(p=0.3, inplace=True), nn.Linear(in_features=1408, out_features= num_classes) ) return model, transforms