import torch

torch.onnx.export(
    final_model, 
    torch.randn(1, 3, 256, 256),
    'models/hot_dog_model_resnet18_256_256.onnx',
    do_constant_folding=True,
    export_params=True,
    input_names=['image_1_3_256_256'],
    output_names=['hot_dog'],
    opset_version=11
)