text: from som.primitives.primitives import Primitives
  from som.vmobjects.primitive   import Primitive
  
  class FramePrimitives(Primitives):
  
      def install_primitives(self):
          def _method(ivkbl, frame, interpreter):
              rcvr = frame.pop()
              frame.push(rcvr.get_method())
          self._install_instance_primitive(Primitive("method",
                                           self._universe, _method))
      
          def _previous_frame(ivkbl, frame, interpreter):
              rcvr = frame.pop()
              frame.push(rcvr.get_previous_frame())
          self._install_instance_primitive(Primitive("previousFrame",
                                           self._universe, _previous_frame))
  