anyone know why I might be this error about TorchInputSpec:

use of unknown declaration 'TorchInputSpec'mojo from:
var session = engine.InferenceSession()
var model = session.load(
model_path,
input_specs = [
engine.TorchInputSpec(
shape=[none, 28, 28], dtype=DType.int32
),

],
)

I've got all the necessary imports, the ai bot is flummoxed