code: def _to_tensor(self):
      data = self.model_inputs[0].zvalue
      return zlayers.GetShape()(data)
  
imports: from zoo.pipeline.api.onnx.mapper.operator_mapper import OperatorMapper
  import zoo.pipeline.api.keras.layers
  import bigdl.nn.layer
label_desc: Use image node_id 2 for calling the ShapeMapper obj's underlying member method code with example usage: obj._to_tensor() and returns: zlayers