code: def test_semantic_segmentation_backbones_registry(backbone):
      backbone = SEMANTIC_SEGMENTATION_BACKBONES.get(backbone)()
      assert backbone
      assert isinstance(backbone, str)
  
imports: import pytest
  from flash.core.utilities.imports import _SEGMENTATION_MODELS_AVAILABLE
  from flash.image.segmentation.backbones import SEMANTIC_SEGMENTATION_BACKBONES
label_desc: Use image node_id 1 for calling a global function with example usage: test_semantic_segmentation_backbones_registry(backbone) without return types