code: def __change_slice_y(self, slider):
      value = int(np.rint(slider.value))
      cs = self.__actor.cross_section
      self.__actor.display_cross_section(cs[0], value, cs[2])
  
imports: import numpy
  from dipy.utils.optpkg import optional_package
  from dipy.viz.horizon.tab import HorizonTab, build_label, color_double_slider, color_single_slider
label_desc: Use image node_id 8 for calling the PeaksTab obj's underlying member method code with example usage: obj.__change_slice_y(slider) without return types