code: def validate_node(causal_graph: DirectedGraph, node: Any) -> None:
      validate_causal_model_assignment(causal_graph, node)
      validate_local_structure(causal_graph, node)
  
imports: from typing import Any, Callable, Optional, Union
  import networkx
  from dowhy.gcm.causal_mechanisms import ConditionalStochasticModel, FunctionalCausalModel, InvertibleFunctionalCausalModel, StochasticModel
  from dowhy.graph import DirectedGraph, HasNodes, get_ordered_predecessors, is_root_node, validate_acyclic, validate_node_in_graph
label_desc: Use image node_id 5 for calling a global function with example usage: validate_node(causal_graph, node) without return types