user: What is I and how is it used in Blender Python scripting?

assistant: class method)](bpy.types.ShaderNodeCombineColor.html#bpy.types.ShaderNodeCombineColor.is_registered_node_type)   - [(bpy.types.ShaderNodeCombineXYZ class method)](bpy.types.ShaderNodeCombineXYZ.html#bpy.types.ShaderNodeCombineXYZ.is_registered_node_type)   - [(bpy.types.ShaderNodeDisplacement class method)](bpy.types.ShaderNodeDisplacement.html#bpy.types.ShaderNodeDisplacement.is_registered_node_type)   - [(bpy.types.ShaderNodeEeveeSpecular class method)](bpy.types.ShaderNodeEeveeSpecular.html#bpy.types.ShaderNodeEeveeSpecular.is_registered_node_type)   - [(bpy.types.ShaderNodeEmission class method)](bpy.types.ShaderNodeEmission.html#bpy.types.ShaderNodeEmission.is_registered_node_type)   - [(bpy.types.ShaderNodeFloatCurve class method)](bpy.types.ShaderNodeFloatCurve.html#bpy.types.ShaderNodeFloatCurve.is_registered_node_type)   - [(bpy.types.ShaderNodeFresnel class method)](bpy.types.ShaderNodeFresnel.html#bpy.types.ShaderNodeFresnel.is_registered_node_type)   - [(bpy.types.ShaderNodeGamma class method)](bpy.types.ShaderNodeGamma.html#bpy.types.ShaderNodeGamma.is_registered_node_type)   - [(bpy.types.ShaderNodeGroup class method)](bpy.types.ShaderNodeGroup.html#bpy.types.ShaderNodeGroup.is_registered_node_type)   - [(bpy.types.ShaderNodeHairInfo class method)](bpy.types.ShaderNodeHairInfo.html#bpy.types.ShaderNodeHairInfo.is_registered_node_type)   - [(bpy.types.ShaderNodeHoldout class method)](bpy.types.ShaderNodeHoldout.html#bpy.types.ShaderNodeHoldout.is_registered_node_type)   - [(bpy.types.ShaderNodeHueSaturation class method)](bpy.types.ShaderNodeHueSaturation.html#bpy.types.ShaderNodeHueSaturation.is_registered_node_type)   - [(bpy.types.ShaderNodeInvert class method)](bpy.types.ShaderNodeInvert.html#bpy.types.ShaderNodeInvert.is_registered_node_type)   - [(bpy.types.ShaderNodeLayerWeight class method)](bpy.types.ShaderNodeLayerWeight.html#bpy.types.ShaderNodeLayerWeight.is_registered_node_type)   - [(bpy.types.ShaderNodeLightFalloff class method)](bpy.types.ShaderNodeLightFalloff.html#bpy.types.ShaderNodeLightFalloff.is_registered_node_type)   - [(bpy.types.ShaderNodeLightPath class method)](bpy.types.ShaderNodeLightPath.html#bpy.types.ShaderNodeLightPath.is_registered_node_type)   - [(bpy.types.ShaderNodeMapping class method)](bpy.types.ShaderNodeMapping.html#bpy.types.ShaderNodeMapping.is_registered_node_type)   - [(bpy.types.ShaderNodeMapRange class method)](bpy.types.ShaderNodeMapRange.html#bpy.types.ShaderNodeMapRange.is_registered_node_type)   - [(bpy.types.ShaderNodeMath class method)](bpy.types.ShaderNodeMath.html#bpy.types.ShaderNodeMath.is_registered_node_type)   - [(bpy.types.ShaderNodeMix class method)](bpy.types.ShaderNodeMix.html#bpy.types.ShaderNodeMix.is_registered_node_type)   - [(bpy.types.ShaderNodeMixRGB class method)](bpy.types.ShaderNodeMixRGB.html#bpy.types.ShaderNodeMixRGB.is_registered_node_type)   - [(bpy.types.ShaderNodeMixShader class method)](bpy.types.ShaderNodeMixShader.html#bpy.types.ShaderNodeMixShader.is_registered_node_type)   - [(bpy.types.ShaderNodeNewGeometry class method)](bpy.types.ShaderNodeNewGeometry.html#bpy.types.ShaderNodeNewGeometry.is_registered_node_type)   - [(bpy.types.ShaderNodeNormal class method)](bpy.types.ShaderNodeNormal.html#bpy.types.ShaderNodeNormal.is_registered_node_type)   - [(bpy.types.ShaderNodeNormalMap class method)](bpy.types.ShaderNodeNormalMap.html#bpy.types.ShaderNodeNormalMap.is_registered_node_type)   - [(bpy.types.ShaderNodeObjectInfo class method)](bpy.types.ShaderNodeObjectInfo.html#bpy.types.ShaderNodeObjectInfo.is_registered_node_type)   - [(bpy.types.ShaderNodeOutputAOV class method)](bpy.types.ShaderNodeOutputAOV.html#bpy.types.ShaderNodeOutputAOV.is_registered_node_type)   - [(bpy.types.ShaderNodeOutputLight class method)](bpy.types.ShaderNodeOutputLight.html#bpy.types.ShaderNodeOutputLight.is_registered_node_type)   - [(bpy.types.ShaderNodeOutputLineStyle class method)](bpy.types.ShaderNodeOutputLineStyle.html#bpy.types.ShaderNodeOutputLineStyle.is_registered_node_type)   - [(bpy.types.ShaderNodeOutputMaterial class method)](bpy.types.ShaderNodeOutputMaterial.html#bpy.types.ShaderNodeOutputMaterial.is_registered_node_type)   - [(bpy.types.ShaderNodeOutputWorld class method)](bpy.types.ShaderNodeOutputWorld.html#bpy.types.ShaderNodeOutputWorld.is_registered_node_type)   - [(bpy.types.ShaderNodeParticleInfo class method)](bpy.types.ShaderNodeParticleInfo.html#bpy.types.ShaderNodeParticleInfo.is_registered_node_type)   - [(bpy.types.ShaderNodePointInfo class method)](bpy.types.ShaderNodePointInfo.html#bpy.types.ShaderNodePointInfo.is_registered_node_type)   - [(bpy.types.ShaderNodeRadialTiling class method)](bpy.types.ShaderNodeRadialTiling.html#bpy.types.ShaderNodeRadialTiling.is_registered_node_type)   - [(bpy.types.ShaderNodeRGB class method)](bpy.types.ShaderNodeRGB.html#bpy.types.ShaderNodeRGB.is_registered_node_type)   - [(bpy.types.ShaderNodeRGBCurve class method)](bpy.types.ShaderNodeRGBCurve.html#bpy.types.ShaderNodeRGBCurve.is_registered_node_type)   - [(bpy.types.ShaderNodeRGBToBW class method)](bpy.types.ShaderNodeRGBToBW.html#bpy.types.ShaderNodeRGBToBW.is_registered_node_type)   - [(bpy.types.ShaderNodeScript class method)](bpy.types.ShaderNodeScript.html#bpy.types.ShaderNodeScript.is_registered_node_type)   - [(bpy.types.ShaderNodeSeparateColor class method)](bpy.types.ShaderNodeSeparateColor.html#bpy.types.ShaderNodeSeparateColor.is_registered_node_type)   - [(bpy.types.ShaderNodeSeparateXYZ class method)](bpy.types.ShaderNodeSeparateXYZ.html#bpy.types.ShaderNodeSeparateXYZ.is_registered_node_type)   - [(bpy.types.ShaderNodeShaderToRGB class method)](bpy.types.ShaderNodeShaderToRGB.html#bpy.types.ShaderNodeShaderToRGB.is_registered_node_type)   - [(bpy.types.ShaderNodeSqueeze class method)](bpy.types.ShaderNodeSqueeze.html#bpy.types.ShaderNodeSqueeze.is_registered_node_type)   - [(bpy.types.ShaderNodeSubsurfaceScattering class method)](bpy.types.ShaderNodeSubsurfaceScattering.html#bpy.types.ShaderNodeSubsurfaceScattering.is_registered_node_type)   - [(bpy.types.ShaderNodeTangent class method)](bpy.types.ShaderNodeTangent.html#bpy.types.ShaderNodeTangent.is_registered_node_type)   - [(bpy.types.ShaderNodeTexBrick class method)](bpy.types.ShaderNodeTexBrick.html#bpy.types.ShaderNodeTexBrick.is_registered_node_type)   - [(bpy.types.ShaderNodeTexChecker class method)](bpy.types.ShaderNodeTexChecker.html#bpy.types.ShaderNodeTexChecker.is_registered_node_type)   - [(bpy.types.ShaderNodeTexCoord class method)](bpy.types.ShaderNodeTexCoord.html#bpy.types.ShaderNodeTexCoord.is_registered_node_type)   - [(bpy.types.ShaderNodeTexEnvironment class method)](bpy.types.ShaderNodeTexEnvironment.html#bpy.types.ShaderNodeTexEnvironment.is_registered_node_type)   - [(bpy.types.ShaderNodeTexGabor class method)](bpy.types.ShaderNodeTexGabor.html#bpy.types.ShaderNodeTexGabor.is_registered_node_type)   - [(bpy.types.ShaderNodeTexGradient class method)](bpy.types.ShaderNodeTexGradient.html#bpy.types.ShaderNodeTexGradient.is_registered_node_type)   - [(bpy.types.ShaderNodeTexIES class method)](bpy.types.ShaderNodeTexIES.html#bpy.types.ShaderNodeTexIES.is_registered_node_type)   - [(bpy.types.ShaderNodeTexImage class method)](bpy.types.ShaderNodeTexImage.html#bpy.types.ShaderNodeTexImage.is_registered_node_type)   - [(bpy.types.ShaderNodeTexMagic class method)](bpy.types.ShaderNodeTexMagic.html#bpy.types.ShaderNodeTexMagic.is_registered_node_type)   - [(bpy.types.ShaderNodeTexNoise class method)](bpy.types.ShaderNodeTexNoise.html#bpy.types.ShaderNodeTexNoise.is_registered_node_type)   - [(bpy.types.ShaderNodeTexSky class method)](bpy.types.ShaderNodeTexSky.html#bpy.types.ShaderNodeTexSky.is_registered_node_type)   - [(bpy.types.ShaderNodeTexVoronoi class method)](bpy.types.ShaderNodeTexVoronoi.html#bpy.types.ShaderNodeTexVoronoi.is_registered_node_type)   - [(bpy.types.ShaderNodeTexWave class method)](bpy.types.ShaderNodeTexWave.html#bpy.types.ShaderNodeTexWave.is_registered_node_type)   - [(bpy.types.ShaderNodeTexWhiteNoise class method)](bpy.types.ShaderNodeTexWhiteNoise.html#bpy.types.ShaderNodeTexWhiteNoise.is_registered_node_type)   - [(bpy.types.ShaderNodeUVAlongStroke class method)](bpy.types.ShaderNodeUVAlongStroke.html#bpy.types.ShaderNodeUVAlongStroke.is_registered_node_type)   - [(bpy.types.ShaderNodeUVMap class method)](bpy.types.ShaderNodeUVMap.html#bpy.types.ShaderNodeUVMap.is_registered_node_type)   - [(bpy.types.ShaderNodeValToRGB class method)](bpy.types.ShaderNodeValToRGB.html#bpy.types.ShaderNodeValToRGB.is_registered_node_type)   - [(bpy.types.ShaderNodeValue class method)](bpy.types.ShaderNodeValue.html#bpy.types.ShaderNodeValue.is_registered_node_type)   - [(bpy.types.ShaderNodeVectorCurve class method)](bpy.types.ShaderNodeVectorCurve.html#bpy.types.ShaderNodeVectorCurve.is_registered_node_type)   - [(bpy.types.ShaderNodeVectorDisplacement class method)](bpy.types.ShaderNodeVectorDisplacement.html#bpy.types.ShaderNodeVectorDisplacement.is_registered_node_type)   - [(bpy.types.ShaderNodeVectorMath class method)](bpy.types.ShaderNodeVectorMath.html#bpy.types.ShaderNodeVectorMath.is_registered_node_type)   - [(bpy.types.ShaderNodeVectorRotate class method)](bpy.types.ShaderNodeVectorRotate.html#bpy.types.ShaderNodeVectorRotate.is_registered_node_type)   - [(bpy.types.ShaderNodeVectorTransform class method)](bpy.types.ShaderNodeVectorTransform.html#bpy.types.ShaderNodeVectorTransform.is_registered_node_type)   - [(bpy.types.ShaderNodeVertexColor class method)](bpy.types.ShaderNodeVertexColor.html#bpy.types.ShaderNodeVertexColor.is_registered_node_type)   - [(bpy.types.ShaderNodeVolumeAbsorption class method)](bpy.types.ShaderNodeVolumeAbsorption.html#bpy.types.ShaderNodeVolumeAbsorption.is_registered_node_type)   - [(bpy.types.ShaderNodeVolumeCoefficients class method)](bpy.types.ShaderNodeVolumeCoefficients.html#bpy.types.ShaderNodeVolumeCoefficients.is_registered_node_type)   - [(bpy.types.ShaderNodeVolumeInfo class method)](bpy.types.ShaderNodeVolumeInfo.html#bpy.types.ShaderNodeVolumeInfo.is_registered_node_type)   - [(bpy.types.ShaderNodeVolumePrincipled class method)](bpy.types.ShaderNodeVolumePrincipled.html#bpy.types.ShaderNodeVolumePrincipled.is_registered_node_type)   - [(bpy.types.ShaderNodeVolumeScatter class method)](bpy.types.ShaderNodeVolumeScatter.html#bpy.types.ShaderNodeVolumeScatter.is_registered_node_type)   - [(bpy.types.ShaderNodeWavelength class method)](bpy.types.ShaderNodeWavelength.html#bpy.types.ShaderNodeWavelength.is_registered_node_type)   - [(bpy.types.ShaderNodeWireframe class method)](bpy.types.ShaderNodeWireframe.html#bpy.types.ShaderNodeWireframe.is_registered_node_type)   - [(bpy.types.TextureNodeAt class method)](bpy.types.TextureNodeAt.html#bpy.types.TextureNodeAt.is_registered_node_type)   - [(bpy.types.TextureNodeBricks class method)](bpy.types.TextureNodeBricks.html#bpy.types.TextureNodeBricks.is_registered_node_type)   - [(bpy.types.TextureNodeChecker class method)](bpy.types.TextureNodeChecker.html#bpy.types.TextureNodeChecker.is_registered_node_type)   - [(bpy.types.TextureNodeCombineColor class method)](bpy.types.TextureNodeCombineColor.html#bpy.types.TextureNodeCombineColor.is_registered_node_type)   - [(bpy.types.TextureNodeCompose class method)](bpy.types.TextureNodeCompose.html#bpy.types.TextureNodeCompose.is_registered_node_type)   - [(bpy.types.TextureNodeCoordinates class method)](bpy.types.TextureNodeCoordinates.html#bpy.types.TextureNodeCoordinates.is_registered_node_type)   - [(bpy.types.TextureNodeCurveRGB class method)](bpy.types.TextureNodeCurveRGB.html#bpy.types.TextureNodeCurveRGB.is_registered_node_type)   - [(bpy.types.TextureNodeCurveTime class method)](bpy.types.TextureNodeCurveTime.html#bpy.types.TextureNodeCurveTime.is_registered_node_type)   - [(bpy.types.TextureNodeDecompose class method)](bpy.types.TextureNodeDecompose.html#bpy.types.TextureNodeDecompose.is_registered_node_type)   - [(bpy.types.TextureNodeDistance class method)](bpy.types.TextureNodeDistance.html#bpy.types.TextureNodeDistance.is_registered_node_type)   - [(bpy.types.TextureNodeGroup class method)](bpy.types.TextureNodeGroup.html#bpy.types.TextureNodeGroup.is_registered_node_type)   - [(bpy.types.TextureNodeHueSaturation class method)](bpy.types.TextureNodeHueSaturation.html#bpy.types.TextureNodeHueSaturation.is_registered_node_type)   - [(bpy.types.TextureNodeImage class method)](bpy.types.TextureNodeImage.html#bpy.types.TextureNodeImage.is_registered_node_type)   - [(bpy.types.TextureNodeInvert class method)](bpy.types.TextureNodeInvert.html#bpy.types.TextureNodeInvert.is_registered_node_type)   - [(bpy.types.TextureNodeMath class method)](bpy.types.TextureNodeMath.html#bpy.types.TextureNodeMath.is_registered_node_type)   - [(bpy.types.TextureNodeMixRGB class method)](bpy.types.TextureNodeMixRGB.html#bpy.types.TextureNodeMixRGB.is_registered_node_type)   - [(bpy.types.TextureNodeOutput class method)](bpy.types.TextureNodeOutput.html#bpy.types.TextureNodeOutput.is_registered_node_type)   - [(bpy.types.TextureNodeRGBToBW class method)](bpy.types.TextureNodeRGBToBW.html#bpy.types.TextureNodeRGBToBW.is_registered_node_type)   - [(bpy.types.TextureNodeRotate class method)](bpy.types.TextureNodeRotate.html#bpy.types.TextureNodeRotate.is_registered_node_type)   - [(bpy.types.TextureNodeScale class method)](bpy.types.TextureNodeScale.html#bpy.types.TextureNodeScale.is_registered_node_type)   - [(bpy.types.TextureNodeSeparateColor class method)](bpy.types.TextureNodeSeparateColor.html#bpy.types.TextureNodeSeparateColor.is_registered_node_type)   - [(bpy.types.TextureNodeTexBlend class method)](bpy.types.TextureNodeTexBlend.html#bpy.types.TextureNodeTexBlend.is_registered_node_type)   - [(bpy.types.TextureNodeTexClouds class method)](bpy.types.TextureNodeTexClouds.html#bpy.types.TextureNodeTexClouds.is_registered_node_type)   - [(bpy.types.TextureNodeTexDistNoise class method)](bpy.types.TextureNodeTexDistNoise.html#bpy.types.TextureNodeTexDistNoise.is_registered_node_type)   - [(bpy.types.TextureNodeTexMagic class method)](bpy.types.TextureNodeTexMagic.html#bpy.types.TextureNodeTexMagic.is_registered_node_type)   - [(bpy.types.TextureNodeTexMarble class method)](bpy.types.TextureNodeTexMarble.html#bpy.types.TextureNodeTexMarble.is_registered_node_type)   - [(bpy.types.TextureNodeTexMusgrave class method)](bpy.types.TextureNodeTexMusgrave.html#bpy.types.TextureNodeTexMusgrave.is_registered_node_type)   - [(bpy.types.TextureNodeTexNoise class method)](bpy.types.TextureNodeTexNoise.html#bpy.types.TextureNodeTexNoise.is_registered_node_type)   - [(bpy.types.TextureNodeTexStucci class method)](bpy.types.TextureNodeTexStucci.html#bpy.types.TextureNodeTexStucci.is_registered_node_type)   - [(bpy.types.TextureNodeTexture class method)](bpy.types.TextureNodeTexture.html#bpy.types.TextureNodeTexture.is_registered_node_type)   - [(bpy.types.TextureNodeTexVoronoi class method)](bpy.types.TextureNodeTexVoronoi.html#bpy.types.TextureNodeTexVoronoi.is_registered_node_type)   - [(bpy.types.TextureNodeTexWood class method)](bpy.types.TextureNodeTexWood.html#bpy.types.TextureNodeTexWood.is_registered_node_type)   - [(bpy.types.TextureNodeTranslate class method)](bpy.types.TextureNodeTranslate.html#bpy.types.TextureNodeTranslate.is_registered_node_type)   - [(bpy.types.TextureNodeValToNor class method)](bpy.types.TextureNodeValToNor.html#bpy.types.TextureNodeValToNor.is_registered_node_type)   - [(bpy.types.TextureNodeValToRGB class method)](bpy.types.TextureNodeValToRGB.html#bpy.types.TextureNodeValToRGB.is_registered_node_type)   - [(bpy.types.TextureNodeViewer class method)](bpy.types.TextureNodeViewer.html#bpy.types.TextureNodeViewer.is_registered_node_type) - [is_repeat() (bpy.types.Operator method)](bpy.types.Operator.html#bpy.types.Operator.is_repeat) - [is_running() (bpy.types.XrSessionState class method)](bpy.types.XrSessionState.html#bpy.types.XrSessionState.is_running) - [is_runtime_data (bpy.types.ID attribute)](bpy.types.ID.html#bpy.types.ID.is_runtime_data) - [is_sequence (bpy.types.CacheFile attribute)](bpy.types.CacheFile.html#bpy.types.CacheFile.is_sequence)   - [(bpy.types.Volume attribute)](bpy.types.Volume.html#bpy.types.Volume.is_sequence) - [is_shadow_catcher (bpy.types.Object attribute)](bpy.types.Object.html#bpy.types.Object.is_shadow_catcher) - [is_singleton (bmesh.types.bmesh.types.BMLayerCollection attribute)](bmesh.types.html#bmesh.types.bmesh.types.BMLayerCollection.is_singleton) - [is_smooth (freestyle.types.freestyle.types.FEdge attribute)](freestyle.types.html#freestyle.types.freestyle.types.FEdge.is_smooth) - [is_solo (bpy.types.BoneCollection attribute)](bpy.types.BoneCollection.html#bpy.types.BoneCollection.is_solo)   - [(bpy.types.NlaTrack attribute)](bpy.types.NlaTrack.html#bpy.types.NlaTrack.is_solo) - [is_start (bpy.types.OperatorStrokeElement attribute)](bpy.types.OperatorStrokeElement.html#bpy.types.OperatorStrokeElement.is_start) - [is_subdir() (in module bpy.path)](bpy.path.html#bpy.path.is_subdir) - [is_syntax_highlight_supported() (bpy.types.SpaceTextEditor method)](bpy.types.SpaceTextEditor.html#bpy.types.SpaceTextEditor.is_syntax_highlight_supported)   - [(bpy.types.Text method)](bpy.types.Text.html#bpy.types.Text.is_syntax_highlight_supported) - [is_system_override (bpy.types.IDOverrideLibrary attribute)](bpy.types.IDOverrideLibrary.html#bpy.types.IDOverrideLibrary.is_system_override) - [is_tool (bpy.types.GeometryNodeTree attribute)](bpy.types.GeometryNodeTree.html#bpy.types.GeometryNodeTree.is_tool) - [is_type_curve (bpy.types.GeometryNodeTree attribute)](bpy.types.GeometryNodeTree.html#bpy.types.GeometryNodeTree.is_type_curve) - [is_type_grease_pencil (bpy.types.GeometryNodeTree attribute)](bpy.types.GeometryNodeTree.html#bpy.types.GeometryNodeTree.is_type_grease_pencil) - [is_type_mesh (bpy.types.GeometryNodeTree attribute)](bpy.types.GeometryNodeTree.html#bpy.types.GeometryNodeTree.is_type_mesh)