code: func _simplify(i interface{}) interface{} {
  
  	if v, ok := i.(*Graph); ok {
  		if v.Len() == 1 && v.Out[0].Len() == 0 {
  			return v.Out[0].This
  		}
  	}
  	return i
  }
docs: // simplify graphs in the form:
  // *
  //   something
  // to a scalar (return something)