code: def move_in_stack(move_up):
      '''Move up or down the stack (for the py-up/py-down command)'''
      frame = Frame.get_selected_python_frame()
      while frame:
          if move_up:
              iter_frame = frame.older()
          else:
              iter_frame = frame.newer()
  
          if not iter_frame:
              break
  
          if iter_frame.is_evalframeex():
              # Result:
              if iter_frame.select():
                  iter_frame.print_summary()
              return
  
          frame = iter_frame
  
      if move_up:
          print 'Unable to find an older python frame'
      else:
          print 'Unable to find a newer python framef move_in_stack(move_up):
      '''Move up or down the stack (for the py-up/py-down command)'''
      frame = Frame.get_selected_python_frame()
      while frame:
          if move_up:
              iter_frame = frame.older()
          else:
              iter_frame = frame.newer()
  
          if not iter_frame:
              break
  
          if iter_frame.is_evalframeex():
              # Result:
              if iter_frame.select():
                  iter_frame.print_summary()
              return
  
          frame = iter_frame
  
      if move_up:
          print 'Unable to find an older python frame'
      else:
          print 'Unable to find a newer python frame'
docs: Move up or down the stack (for the py-up/py-down command)