code: def _module_name_from_previous_frame(num_frames_back):
      
      frm = inspect.stack()[num_frames_back + 1]
      return inspect.getmodule(frm[0]).__name__
docs: Returns the module name associated with a frame `num_frames_back` in the
      call stack. This function adds 1 to account for itself, so `num_frames_back`
      should be given relative to the caller.