code: def test_update_gl_state():
      node = vispy.visuals.MeshVisual()
  
      og_gl_state = node._vshare.gl_state.copy()
      assert og_gl_state
      og_gl_state["blend"] = False
  
      node.update_gl_state(blend=True)
  
      # check that the state was updated
      assert node._vshare.gl_state.pop("blend") != og_gl_state.pop(
          "blend"
      )
      # the rest of the state should be unchanged
      assert node._vshare.gl_state == og_gl_state
  
file_path: vispy/vispy/scene/tests/test_visuals.py
imports: import pytest
  from vispy.scene import visuals, Node
  from vispy.scene.visuals import VisualNode
  import vispy.visuals
label_desc: Use image node_id 6 for calling a global function with example usage: test_update_gl_state() without return types