Creating a new label class in Arc Pro using the arcpy CIM

[WilliamParra]

I am attempting to create a new label class for a layer using the arcpy CIM, code below. The new label class gets created, but ArcGIS Pro immediately crashes when I attempt to interact with it in the GUI. I have tried in the python window and in a script. 

aprx = arcpy.mp.ArcGISProject('CURRENT')
m = aprx.listMaps("Map")[0]
lyr = m.listLayers("SOME LAYER")[0]
ldef = lyr.getDefinition('V2')

newlblclass = arcpy.cim.CreateCIMObjectFromClassName('CIMLabelClass','V2')
newlblclass.name = "NEW CLASS"
newlblclass.visibility = True
ldef.labelClasses.append(newlblclass)
lyr.setDefinition(ldef)

[DuncanHornby · Accepted solution]

May be there are required properties that need setting? All you set is the name and visibility, but what about the field that the label is derived from?

[WilliamParra · Accepted solution]

Correct. After researching there are many "nested" CIMobjects that make up a label class cim object. All of these objects need to be created and assigned in order for the label class object to function properly. 

Reference: https://pro.arcgis.com/en/pro-app/arcpy/mapping/python-cim-access.htm