code: def init(
      model: Model[InT, OutT],
      X: Optional[InT] = None,
      Y: Optional[OutT] = None,
  ) -> None:
      model.layers[0].initialize(
          _flatten(X) if X is not None else None,
          model.layers[0].ops.xp.hstack(Y) if Y is not None else None,
      )
  
imports: from typing import Any, Callable, List, Optional, Sequence, Tuple, TypeVar, cast
  from ..config import registry
  from ..model import Model
  from ..types import ArrayXd, ListXd
label_desc: Use image node_id 4 for calling a global function with example usage: init(model, X, Y) without return types