code: def tuplify(
      layer1: Model[InT, Any], layer2: Model[InT, Any], *layers
  ) -> Model[InT, Tuple]:
      """Send a separate copy of the input to each child layer, and join the
      outputs of the children into a tuple on the way out.
  
      Typically used to provide both modified data and the original input to a
      downstream layer.
      """
  
      layers = (layer1, layer2) + layers
      names = [layer.name for layer in layers]
      return Model(
          "tuple(" + ", ".join(names) + ")",
          tuplify_forward,
          init=init,
          layers=layers,
          dims={"nI": None},
      )
  
imports: from typing import Any, Optional, Tuple, TypeVar
  from ..config import registry
  from ..model import Model
label_desc: Use image node_id 1 for calling a global function with example usage: tuplify(layer1, layer2) and returns: Model