reset a custom PropertyGroup of an object to initial state I have created a PropertyGroup as follows:

# Define property groups...
class ObjectPropGroup(bpy.types.PropertyGroup):
    edge_display = BoolProperty(default=False, name="Edge Display")

#initialize custom property groups...
bpy.types.Object.ObjectProp   = PointerProperty(type = ObjectPropGroup)


When i now create a new object obj and then look into the custom properties list, ObjectProp is not listed. But as soon as i add a property to the group:

obj.ObjectProp.edge_display=True


now the ObjectProp appears in the list of custom properties of the object.
This is all good so far. But now i run into a small problem when i want to cleanup the object and remove all elements from ObjectProp. So what i do for now is:

for key in obj.ObjectProp.keys(): del bpy.context.object.ObjectProp[key]


This works as expected and deletes all data. However the ObjectProp itself keeps in the list of custom properties with an empty data set {} Is there a way reset obj into its initial state so that ObjectProp is no longer shown in the custom properties list? I tried the easy way but that failed:

del obj.ObjectProp
Traceback (most recent call last):
  File "&lt;blender_console&gt;", line 1, in &lt;module&gt;
AttributeError: bpy_struct: attribute "ObjectProp" from "Object" is read-only


Is there a solution?
The answer is so stupid simple:

del obj['ObjectProp']


However i hope this question is still helpful for some others.