Is_registered attribute for Macro, Gizmo, GizmoGroup

Is there a way to check if the classes mentioned above are already registered?

To avoid errors I usually check all the other classes (opeartors, panels) if they’re actually registered with is_registered before unregistering them but Macro, Gizmo, GizmoGroup lack this type of attribute.

import bpy
class TestMacro(bpy.types.Macro):
    bl_idname = 'test.macro'
    bl_label = 'test macro'

print(hasattr(TestMacro, 'is_registered')) # False