class_docstr: Default Cairo drawer object for dendrograms.
docstr: Calculates the amount of space needed for drawing an
  individual vertex at the bottom of the dendrogram.
docstr_tok: ["Calculates","the","amount","of","space","needed","for","drawing","an","individual","vertex","at","the","bottom","of","the","dendrogram","."]
code: def _item_box_size(dendro, context, horiz, idx):
      """Calculates the amount of space needed for drawing an
      individual vertex at the bottom of the dendrogram."""
      if dendro._names is None or dendro._names[idx] is None:
          x_bearing, _, _, height, x_advance, _ = context.text_extents(
              ""
          )
      else:
          x_bearing, _, _, height, x_advance, _ = context.text_extents(
              str(dendro._names[idx])
          )
  
      if horiz:
          return x_advance - x_bearing, height
      return height, x_advance - x_bearing
  
file_path: python-igraph/src/igraph/drawing/cairo/dendrogram.py
imports: from math import pi
  from igraph.drawing.utils import str_to_orientation
  from .base import AbstractCairoDrawer
label_desc: Use image node_id 2 for calling the CairoDendrogramDrawer obj's underlying member method code with example usage: obj._item_box_size(dendro, context, horiz, idx) and returns: height,  unknown, unknown,  height