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

assistant: reestyle.types.Iterator attribute)](freestyle.types.html#freestyle.types.freestyle.types.Iterator.is_begin) - [is_bound (gpu.types.GPUFrameBuffer attribute)](gpu.types.html#gpu.types.GPUFrameBuffer.is_bound) - [is_boundary (bmesh.types.bmesh.types.BMEdge attribute)](bmesh.types.html#bmesh.types.bmesh.types.BMEdge.is_boundary)   - [(bmesh.types.bmesh.types.BMVert attribute)](bmesh.types.html#bmesh.types.bmesh.types.BMVert.is_boundary) - [is_cache_baking_any (bpy.types.FluidDomainSettings attribute)](bpy.types.FluidDomainSettings.html#bpy.types.FluidDomainSettings.is_cache_baking_any) - [is_cache_baking_data (bpy.types.FluidDomainSettings attribute)](bpy.types.FluidDomainSettings.html#bpy.types.FluidDomainSettings.is_cache_baking_data) - [is_cache_baking_guide (bpy.types.FluidDomainSettings attribute)](bpy.types.FluidDomainSettings.html#bpy.types.FluidDomainSettings.is_cache_baking_guide) - [is_cache_baking_mesh (bpy.types.FluidDomainSettings attribute)](bpy.types.FluidDomainSettings.html#bpy.types.FluidDomainSettings.is_cache_baking_mesh) - [is_cache_baking_noise (bpy.types.FluidDomainSettings attribute)](bpy.types.FluidDomainSettings.html#bpy.types.FluidDomainSettings.is_cache_baking_noise) - [is_cache_baking_particles (bpy.types.FluidDomainSettings attribute)](bpy.types.FluidDomainSettings.html#bpy.types.FluidDomainSettings.is_cache_baking_particles) - [is_closed (freestyle.types.freestyle.types.ViewEdge attribute)](freestyle.types.html#freestyle.types.freestyle.types.ViewEdge.is_closed) - [is_contiguous (bmesh.types.bmesh.types.BMEdge attribute)](bmesh.types.html#bmesh.types.bmesh.types.BMEdge.is_contiguous) - [is_convex (bmesh.types.bmesh.types.BMEdge attribute)](bmesh.types.html#bmesh.types.bmesh.types.BMEdge.is_convex)   - [(bmesh.types.bmesh.types.BMLoop attribute)](bmesh.types.html#bmesh.types.bmesh.types.BMLoop.is_convex) - [is_data (bpy.types.ColorManagedInputColorspaceSettings attribute)](bpy.types.ColorManagedInputColorspaceSettings.html#bpy.types.ColorManagedInputColorspaceSettings.is_data) - [is_deform_modified() (bpy.types.Object method)](bpy.types.Object.html#bpy.types.Object.is_deform_modified) - [is_dirty (bpy.types.Preferences attribute)](bpy.types.Preferences.html#bpy.types.Preferences.is_dirty) - [is_empty (freestyle.types.freestyle.types.Curve attribute)](freestyle.types.html#freestyle.types.freestyle.types.Curve.is_empty) - [is_end (freestyle.types.freestyle.types.Iterator attribute)](freestyle.types.html#freestyle.types.freestyle.types.Iterator.is_end) - [is_expanded (bpy.types.BoneCollection attribute)](bpy.types.BoneCollection.html#bpy.types.BoneCollection.is_expanded)   - [(bpy.types.GreasePencilLayerGroup attribute)](bpy.types.GreasePencilLayerGroup.html#bpy.types.GreasePencilLayerGroup.is_expanded) - [is_extended() (bpy.types.Header class method)](bpy.types.Header.html#bpy.types.Header.is_extended)   - [(bpy.types.Menu class method)](bpy.types.Menu.html#bpy.types.Menu.is_extended)   - [(bpy.types.Panel class method)](bpy.types.Panel.html#bpy.types.Panel.is_extended)   - [(bpy.types.UIList class method)](bpy.types.UIList.html#bpy.types.UIList.is_extended) - [is_frozen (mathutils.Color attribute)](mathutils.html#mathutils.Color.is_frozen)   - [(mathutils.Euler attribute)](mathutils.html#mathutils.Euler.is_frozen)   - [(mathutils.Matrix attribute)](mathutils.html#mathutils.Matrix.is_frozen)   - [(mathutils.Quaternion attribute)](mathutils.html#mathutils.Quaternion.is_frozen)   - [(mathutils.Vector attribute)](mathutils.html#mathutils.Vector.is_frozen) - [is_holdout (bpy.types.Object attribute)](bpy.types.Object.html#bpy.types.Object.is_holdout) - [is_icon_custom (bpy.types.ImagePreview attribute)](bpy.types.ImagePreview.html#bpy.types.ImagePreview.is_icon_custom) - [is_identity (mathutils.Matrix attribute)](mathutils.html#mathutils.Matrix.is_identity) - [is_image_custom (bpy.types.ImagePreview attribute)](bpy.types.ImagePreview.html#bpy.types.ImagePreview.is_image_custom) - [is_in_hierarchy (bpy.types.IDOverrideLibrary attribute)](bpy.types.IDOverrideLibrary.html#bpy.types.IDOverrideLibrary.is_in_hierarchy) - [is_incoming (freestyle.types.freestyle.types.AdjacencyIterator attribute)](freestyle.types.html#freestyle.types.freestyle.types.AdjacencyIterator.is_incoming) - [is_incrementing (freestyle.types.freestyle.types.ChainingIterator attribute)](freestyle.types.html#freestyle.types.freestyle.types.ChainingIterator.is_incrementing) - [is_inspect_output (bpy.types.NodeTreeInterfaceSocket attribute)](bpy.types.NodeTreeInterfaceSocket.html#bpy.types.NodeTreeInterfaceSocket.is_inspect_output) - [is_job_running() (in module bpy.app)](bpy.app.html#bpy.app.is_job_running) - [is_keyed (bpy.types.MovieTrackingMarker attribute)](bpy.types.MovieTrackingMarker.html#bpy.types.MovieTrackingMarker.is_keyed) - [is_manifold (bmesh.types.bmesh.types.BMEdge attribute)](bmesh.types.html#bmesh.types.bmesh.types.BMEdge.is_manifold)   - [(bmesh.types.bmesh.types.BMVert attribute)](bmesh.types.html#bmesh.types.bmesh.types.BMVert.is_manifold) - [is_mode_edit (bpy.types.GeometryNodeTree attribute)](bpy.types.GeometryNodeTree.html#bpy.types.GeometryNodeTree.is_mode_edit) - [is_mode_object (bpy.types.GeometryNodeTree attribute)](bpy.types.GeometryNodeTree.html#bpy.types.GeometryNodeTree.is_mode_object) - [is_mode_paint (bpy.types.GeometryNodeTree attribute)](bpy.types.GeometryNodeTree.html#bpy.types.GeometryNodeTree.is_mode_paint) - [is_mode_sculpt (bpy.types.GeometryNodeTree attribute)](bpy.types.GeometryNodeTree.html#bpy.types.GeometryNodeTree.is_mode_sculpt) - [is_modified (bpy.types.MotionPath attribute)](bpy.types.MotionPath.html#bpy.types.MotionPath.is_modified) - [is_modified() (bpy.types.Object method)](bpy.types.Object.html#bpy.types.Object.is_modified) - [is_modifier (bpy.types.GeometryNodeTree attribute)](bpy.types.GeometryNodeTree.html#bpy.types.GeometryNodeTree.is_modifier) - [is_muted (bpy.types.NodeLink attribute)](bpy.types.NodeLink.html#bpy.types.NodeLink.is_muted) - [is_negative (mathutils.Matrix attribute)](mathutils.html#mathutils.Matrix.is_negative) - [is_open (bpy.types.CollectionExport attribute)](bpy.types.CollectionExport.html#bpy.types.CollectionExport.is_open)   - [(bpy.types.LayoutPanelState attribute)](bpy.types.LayoutPanelState.html#bpy.types.LayoutPanelState.is_open)   - [(bpy.types.NodesModifierPanel attribute)](bpy.types.NodesModifierPanel.html#bpy.types.NodesModifierPanel.is_open) - [is_orthogonal (mathutils.Matrix attribute)](mathutils.html#mathutils.Matrix.is_orthogonal) - [is_orthogonal_axis_vectors (mathutils.Matrix attribute)](mathutils.html#mathutils.Matrix.is_orthogonal_axis_vectors) - [is_orthographic_side_view (bpy.types.RegionView3D attribute)](bpy.types.RegionView3D.html#bpy.types.RegionView3D.is_orthographic_side_view) - [is_panel_toggle (bpy.types.NodeTreeInterfaceSocket attribute)](bpy.types.NodeTreeInterfaceSocket.html#bpy.types.NodeTreeInterfaceSocket.is_panel_toggle) - [is_perspective (bpy.types.RegionView3D attribute)](bpy.types.RegionView3D.html#bpy.types.RegionView3D.is_perspective) - [is_pinned (bpy.types.SpaceSpreadsheet attribute)](bpy.types.SpaceSpreadsheet.html#bpy.types.SpaceSpreadsheet.is_pinned) - [is_poly_clockwise() (in module freestyle.utils)](freestyle.utils.html#freestyle.utils.is_poly_clockwise) - [is_preview (bpy.types.RenderEngine attribute)](bpy.types.RenderEngine.html#bpy.types.RenderEngine.is_preview) - [is_property_hidden() (bpy.types.bpy_struct method)](bpy.types.bpy_struct.html#bpy.types.bpy_struct.is_property_hidden) - [is_property_overridable_library() (bpy.types.bpy_struct method)](bpy.types.bpy_struct.html#bpy.types.bpy_struct.is_property_overridable_library) - [is_property_readonly() (bpy.types.bpy_struct method)](bpy.types.bpy_struct.html#bpy.types.bpy_struct.is_property_readonly) - [is_property_set() (bpy.types.bpy_struct method)](bpy.types.bpy_struct.html#bpy.types.bpy_struct.is_property_set) - [is_registered() (in module bpy.app.timers)](bpy.app.timers.html#bpy.app.timers.is_registered) - [is_registered_node_type() (bpy.types.CompositorNodeAlphaOver class method)](bpy.types.CompositorNodeAlphaOver.html#bpy.types.CompositorNodeAlphaOver.is_registered_node_type)   - [(bpy.types.CompositorNodeAntiAliasing class method)](bpy.types.CompositorNodeAntiAliasing.html#bpy.types.CompositorNodeAntiAliasing.is_registered_node_type)   - [(bpy.types.CompositorNodeBilateralblur class method)](bpy.types.CompositorNodeBilateralblur.html#bpy.types.CompositorNodeBilateralblur.is_registered_node_type)   - [(bpy.types.CompositorNodeBlur class method)](bpy.types.CompositorNodeBlur.html#bpy.types.CompositorNodeBlur.is_registered_node_type)   - [(bpy.types.CompositorNodeBokehBlur class method)](bpy.types.CompositorNodeBokehBlur.html#bpy.types.CompositorNodeBokehBlur.is_registered_node_type)   - [(bpy.types.CompositorNodeBokehImage class method)](bpy.types.CompositorNodeBokehImage.html#bpy.types.CompositorNodeBokehImage.is_registered_node_type)   - [(bpy.types.CompositorNodeBoxMask class method)](bpy.types.CompositorNodeBoxMask.html#bpy.types.CompositorNodeBoxMask.is_registered_node_type)   - [(bpy.types.CompositorNodeBrightContrast class method)](bpy.types.CompositorNodeBrightContrast.html#bpy.types.CompositorNodeBrightContrast.is_registered_node_type)   - [(bpy.types.CompositorNodeChannelMatte class method)](bpy.types.CompositorNodeChannelMatte.html#bpy.types.CompositorNodeChannelMatte.is_registered_node_type)   - [(bpy.types.CompositorNodeChromaMatte class method)](bpy.types.CompositorNodeChromaMatte.html#bpy.types.CompositorNodeChromaMatte.is_registered_node_type)   - [(bpy.types.CompositorNodeColorBalance class method)](bpy.types.CompositorNodeColorBalance.html#bpy.types.CompositorNodeColorBalance.is_registered_node_type)   - [(bpy.types.CompositorNodeColorCorrection class method)](bpy.types.CompositorNodeColorCorrection.html#bpy.types.CompositorNodeColorCorrection.is_registered_node_type)   - [(bpy.types.CompositorNodeColorMatte class method)](bpy.types.CompositorNodeColorMatte.html#bpy.types.CompositorNodeColorMatte.is_registered_node_type)   - [(bpy.types.CompositorNodeColorSpill class method)](bpy.types.CompositorNodeColorSpill.html#bpy.types.CompositorNodeColorSpill.is_registered_node_type)   - [(bpy.types.CompositorNodeCombineColor class method)](bpy.types.CompositorNodeCombineColor.html#bpy.types.CompositorNodeCombineColor.is_registered_node_type)   - [(bpy.types.CompositorNodeConvertColorSpace class method)](bpy.types.CompositorNodeConvertColorSpace.html#bpy.types.CompositorNodeConvertColorSpace.is_registered_node_type)   - [(bpy.types.CompositorNodeConvertToDisplay class method)](bpy.types.CompositorNodeConvertToDisplay.html#bpy.types.CompositorNodeConvertToDisplay.is_registered_node_type)   - [(bpy.types.CompositorNodeConvolve class method)](bpy.types.CompositorNodeConvolve.html#bpy.types.CompositorNodeConvolve.is_registered_node_type)   - [(bpy.types.CompositorNodeCornerPin class method)](bpy.types.CompositorNodeCornerPin.html#bpy.types.CompositorNodeCornerPin.is_registered_node_type)   - [(bpy.types.CompositorNodeCrop class method)](bpy.types.CompositorNodeCrop.html#bpy.types.CompositorNodeCrop.is_registered_node_type)   - [(bpy.types.CompositorNodeCryptomatte class method)](bpy.types.CompositorNodeCryptomatte.html#bpy.types.CompositorNodeCryptomatte.is_registered_node_type)   - [(bpy.types.CompositorNodeCryptomatteV2 class method)](bpy.types.CompositorNodeCryptomatteV2.html#bpy.types.CompositorNodeCryptomatteV2.is_registered_node_type)   - [(bpy.types.CompositorNodeCurveRGB class method)](bpy.types.CompositorNodeCurveRGB.html#bpy.types.CompositorNodeCurveRGB.is_registered_node_type)   - [(bpy.types.CompositorNodeDBlur class method)](bpy.types.CompositorNodeDBlur.html#bpy.types.CompositorNodeDBlur.is_registered_node_type)   - [(bpy.types.CompositorNodeDefocus class method)](bpy.types.CompositorNodeDefocus.html#bpy.types.CompositorNodeDefocus.is_registered_node_type)   - [(bpy.types.CompositorNodeDenoise class method)](bpy.types.CompositorNodeDenoise.html#bpy.types.CompositorNodeDenoise.is_registered_node_type)   - [(bpy.types.CompositorNodeDespeckle class method)](bpy.types.CompositorNodeDespeckle.html#bpy.types.CompositorNodeDespeckle.is_registered_node_type)   - [(bpy.types.CompositorNodeDiffMatte class method)](bpy.types.CompositorNodeDiffMatte.html#bpy.types.CompositorNodeDiffMatte.is_registered_node_type)   - [(bpy.types.CompositorNodeDilateErode class method)](bpy.types.CompositorNodeDilateErode.html#bpy.types.CompositorNodeDilateErode.is_registered_node_type)   - [(bpy.types.CompositorNodeDisplace class method)](bpy.types.CompositorNodeDisplace.html#bpy.types.CompositorNodeDisplace.is_registered_node_type)   - [(bpy.types.CompositorNodeDistanceMatte class method)](bpy.types.CompositorNodeDistanceMatte.html#bpy.types.CompositorNodeDistanceMatte.is_registered_node_type)   - [(bpy.types.CompositorNodeDoubleEdgeMask class method)](bpy.types.CompositorNodeDoubleEdgeMask.html#bpy.types.CompositorNodeDoubleEdgeMask.is_registered_node_type)   - [(bpy.types.CompositorNodeEllipseMask class method)](bpy.types.CompositorNodeEllipseMask.html#bpy.types.CompositorNodeEllipseMask.is_registered_node_type)   - [(bpy.types.CompositorNodeExposure class method)](bpy.types.CompositorNodeExposure.html#bpy.types.CompositorNodeExposure.is_registered_node_type)   - [(bpy.types.CompositorNodeFilter class method)](bpy.types.CompositorNodeFilter.html#bpy.types.CompositorNodeFilter.is_registered_node_type)   - [(bpy.types.CompositorNodeFlip class method)](bpy.types.CompositorNodeFlip.html#bpy.types.CompositorNodeFlip.is_registered_node_type)   - [(bpy.types.CompositorNodeGamma class method)](bpy.types.CompositorNodeGamma.html#bpy.types.CompositorNodeGamma.is_registered_node_type)   - [(bpy.types.CompositorNodeGlare class method)](bpy.types.CompositorNodeGlare.html#bpy.types.CompositorNodeGlare.is_registered_node_type)   - [(bpy.types.CompositorNodeGroup class method)](bpy.types.CompositorNodeGroup.html#bpy.types.CompositorNodeGroup.is_registered_node_type)   - [(bpy.types.CompositorNodeHueCorrect class method)](bpy.types.CompositorNodeHueCorrect.html#bpy.types.CompositorNodeHueCorrect.is_registered_node_type)   - [(bpy.types.CompositorNodeHueSat class method)](bpy.types.CompositorNodeHueSat.html#bpy.types.CompositorNodeHueSat.is_registered_node_type)   - [(bpy.types.CompositorNodeIDMask class method)](bpy.types.CompositorNodeIDMask.html#bpy.types.CompositorNodeIDMask.is_registered_node_type)   - [(bpy.types.CompositorNodeImage class method)](bpy.types.CompositorNodeImage.html#bpy.types.CompositorNodeImage.is_registered_node_type)   - [(bpy.types.CompositorNodeImageCoordinates class method)](bpy.types.CompositorNodeImageCoordinates.html#bpy.types.CompositorNodeImageCoordinates.is_registered_node_type)   - [(bpy.types.CompositorNodeImageInfo class method)](bpy.types.CompositorNodeImageInfo.html#bpy.types.CompositorNodeImageInfo.is_registered_node_type)   - [(bpy.types.CompositorNodeInpaint class method)](bpy.types.CompositorNodeInpaint.html#bpy.types.CompositorNodeInpaint.is_registered_node_type)   - [(bpy.types.CompositorNodeInvert class method)](bpy.types.CompositorNodeInvert.html#bpy.types.CompositorNodeInvert.is_registered_node_type)   - [(bpy.types.CompositorNodeKeying class method)](bpy.types.CompositorNodeKeying.html#bpy.types.CompositorNodeKeying.is_registered_node_type)   - [(bpy.types.CompositorNodeKeyingScreen class method)](bpy.types.CompositorNodeKeyingScreen.html#bpy.types.CompositorNodeKeyingScreen.is_registered_node_type)   - [(bpy.types.CompositorNodeKuwahara class method)](bpy.types.CompositorNodeKuwahara.html#bpy.types.CompositorNodeKuwahara.is_registered_node_type)   - [(bpy.types.CompositorNodeLensdist class method)](bpy.types.CompositorNodeLensdist.html#bpy.types.CompositorNodeLensdist.is_registered_node_type)   - [(bpy.types.CompositorNodeLevels class method)](bpy.types.CompositorNodeLevels.html#bpy.types.CompositorNodeLevels.is_registered_node_type)   - [(bpy.types.CompositorNodeLumaMatte class method)](bpy.types.CompositorNodeLumaMatte.html#bpy.types.CompositorNodeLumaMatte.is_registered_node_type)   - [(bpy.types.CompositorNodeMapUV class method)](bpy.types.CompositorNodeMapUV.html#bpy.types.CompositorNodeMapUV.is_registered_node_type)   - [(bpy.types.CompositorNodeMask class method)](bpy.types.CompositorNodeMask.html#bpy.types.CompositorNodeMask.is_registered_node_type)   - [(bpy.types.CompositorNodeMovieClip class method)](bpy.types.CompositorNodeMovieClip.html#bpy.types.CompositorNodeMovieClip.is_registered_node_type)   - [(bpy.types.CompositorNodeMovieDistortion class method)](bpy.types.CompositorNodeMovieDistortion.html#bpy.types.CompositorNodeMovieDistortion.is_registered_node_type)   - [(bpy.types.CompositorNodeNormal class method)](bpy.types.CompositorNodeNormal.html#bpy.types.CompositorNodeNormal.is_registered_node_type)   - [(bpy.types.CompositorNodeNormalize class method)](bpy.types.CompositorNodeNormalize.html#bpy.types.CompositorNodeNormalize.is_registered_node_type)   - [(bpy.types.CompositorNodeOutputFile class method)](bpy.types.CompositorNodeOutputFile.html#bpy.types.CompositorNodeOutputFile.is_registered_node_type)   - [(bpy.types.CompositorNodePixelate class method)](bpy.types.CompositorNodePixelate.html#bpy.types.CompositorNodePixelate.is_registered_node_type)   - [(bpy.types.CompositorNodePlaneTrackDeform class method)](bpy.types.CompositorNodePlaneTrackDeform.html#bpy.types.CompositorNodePlaneTrackDeform.is_registered_node_type)   - [(bpy.types.CompositorNodePosterize class method)](bpy.types.CompositorNodePosterize.html#bpy.types.CompositorNodePosterize.is_registered_node_type)   - [(bpy.types.CompositorNodePremulKey class method)](bpy.types.CompositorNodePremulKey.html#bpy.types.CompositorNodePremulKey.is_registered_node_type)   - [(bpy.types.CompositorNodeRelativeToPixel class method)](bpy.types.CompositorNodeRelativeToPixel.html#bpy.types.CompositorNodeRe