code: def setOverlayTransformOverlayRelative(self, ulOverlayHandle, ulOverlayHandleParent):
          
  
          fn = self.function_table.setOverlayTransformOverlayRelative
          pmatParentOverlayToOverlayTransform = HmdMatrix34_t()
          result = fn(ulOverlayHandle, ulOverlayHandleParent, byref(pmatParentOverlayToOverlayTransform))
          return result, pmatParentOverlayToOverlayTransform
docs: Sets the transform to relative to the transform of the specified overlay. This overlays visibility will also track the parents visibility