code: def get_radii(self):
          
          bb = self.profile.val().BoundingBox()
          return (bb.xmin, bb.xmax)
docs: Get the inner and outer radii of the thread.
  
          :return: (<inner radius>, <outer radius>)
          :rtype: :class:`tuple`
  
          .. note::
  
              Ideally this method is overridden in inheriting classes to
              mathematically determine the radii.
  
              Default action is to generate the profile, then use the
              bounding box to determine min & max radii. However this method is
              prone to small numeric error.