When passing an EnumProperty value to the function parameters, just like with direct assignment, we must always specify the value from the constant list exactly, otherwise, Blender will throw an error.
When we create complex shaders in Blender, consisting of a large number of node groups, the menu for adding new nodes to the material gets clogged up very quickly. In a long list of node groups, it becomes difficult to find the one we need, and even a search does not always save the day. The list of node groups in the menu can be reduced by hiding unnecessary node group names from it.