code: def init_artists(self, ax, plot_args, plot_kwargs):
      fontsize = plot_kwargs.pop("label_text_font_size", 8)
      artists = super().init_artists(ax, plot_args, plot_kwargs)
      groups = [g for g in self._style_groups if g != "node"]
      node_opts = filter_styles(
          plot_kwargs, "node", groups, ("s", "node_s")
      )
      rects = [Rectangle(**rect) for rect in plot_args["rects"]]
      if "vmin" in node_opts:
          node_opts["clim"] = node_opts.pop("vmin"), node_opts.pop(
              "vmax"
          )
      if "c" in node_opts:
          node_opts["array"] = node_opts.pop("c")
      artists["rects"] = ax.add_collection(
          PatchCollection(rects, **node_opts)
      )
      plot_kwargs["label_text_font_size"] = fontsize
      artists["labels"] = self._update_labels(
          ax, plot_args, plot_kwargs
      )
      return artists
  
file_path: holoviews/holoviews/plotting/mpl/sankey.py
imports: import param
  from matplotlib.collections import PatchCollection
  from matplotlib.patches import Rectangle
  from ...core.util import max_range
  from ...util.transform import dim
  from .graphs import GraphPlot
  from .util import filter_styles
label_desc: Use image node_id 4 for calling the SankeyPlot obj's underlying member method code with example usage: obj.init_artists(ax, plot_args, plot_kwargs) and returns: artists