code: def ni_method(self, length=None, offset=None, **kwargs):
      close = self._get_column(kwargs.pop("close", "close"))
      result = ni(close=close, length=length, offset=offset, **kwargs)
      return self._post_process(result, **kwargs)
  
label_desc: Use image node_id 2 for calling a global function with example usage: ni_method(length, offset) and returns: self