code: def _load_graph_backbone(
      model_name: str,
      in_channels: int,
      hidden_channels: int = 512,
      num_layers: int = 4,
  ):
      model = MODELS[model_name]
      return model(in_channels, hidden_channels, num_layers)
  
imports: from functools import partial
  from flash.core.registry import FlashRegistry
  from flash.core.utilities.imports import _TOPIC_GRAPH_AVAILABLE
  from flash.core.utilities.providers import _PYTORCH_GEOMETRIC
label_desc: Use image node_id 1 for calling a global function with example usage: _load_graph_backbone(model_name, in_channels, hidden_channels, num_layers) and returns: model