code: def _attach(self, visual):
      super(ZColormapFilter, self)._attach(visual)
      self.vshader["position"] = visual.shared_program.vert["position"]
  
imports: from .base_filter import Filter
  from ..shaders import Function, Varying
  from ...color import colormap, Color
label_desc: Use image node_id 2 for calling the ZColormapFilter obj's underlying member method code with example usage: obj._attach(visual) without return types