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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _get_attribute_tensors(onnx_model_proto):
 # type: (ModelProto) -> Iterable[TensorProto] """Create an iterator of tensors from node attributes of an ONNX model."""

    for node in onnx_model_proto.graph.node:
        for attribute in node.attribute:
            if attribute.HasField("t"):
                yield attribute.t
            for tensor in attribute.tensors:
                yield tensor