class_docstr: The classic Sugiyama layout aka layered layout.
  
  - See https://en.wikipedia.org/wiki/Layered_graph_drawing
  - Excellent explanation: https://www.youtube.com/watch?v=Z0RGCWxvCxA
  
  
  **Attributes**
      - dirvh (int): the current aligment state for alignment policy:
               dirvh=0 -> dirh=+1, dirv=-1: leftmost upper
               dirvh=1 -> dirh=-1, dirv=-1: rightmost upper
               dirvh=2 -> dirh=+1, dirv=+1: leftmost lower
               dirvh=3 -> dirh=-1, dirv=+1: rightmost lower
      - order_iter (int): the default number of layer placement iterations
      - order_attr (str): set attribute name used for layer ordering
      - xspace (int): horizontal space between vertices in a layer
      - yspace (int): vertical space between layers
      - dw (int): default width of a vertex
      - dh (int): default height of a vertex
      - g (GraphBase): the graph component reference
      - layers (list[sugiyama.layer.Layer]): the list of layers
      - layoutVertices (dict): associate vertex (possibly dummy) with their sugiyama attributes
      - ctrls (dict): associate edge with all its vertices (including dummies)
      - dag (bool): the current acyclic state
      - init_done (bool): True if things were initialized
  
  **Example**
  
      ::
  
          g = nx.generators.connected_watts_strogatz_graph(1000, 2, 0.3)
          # render
          SugiyamaLayout.draw(g)
          # positions
          positions_dictionary = SugiyamaLayout.arrange(g)
docstr: Creates a DummyVertex at layer r inserted in the ctrl dict of the associated edge and layer.
  
  **Arguments**
      - r (int): layer value
      - ctrl (dict): the edge's control vertices
     
  **Returns**
        sugiyama.DummyVertex : the created DummyVertex.
docstr_tok: ["Creates","a","DummyVertex","at","layer","r","inserted","in","the","ctrl","dict","of","the","associated","edge","and","layer",".","*","*","Arguments","*","*","-","r","(","int",")",":","layer","value","-","ctrl","(","dict",")",":","the","edge","'s","control","vertices","*","*","Returns","*","*","sugiyama.DummyVertex",":","the","created","DummyVertex","."]
code: def dummyctrl(self, r, control_vertices):
      """
      Creates a DummyVertex at layer r inserted in the ctrl dict of the associated edge and layer.
  
      **Arguments**
          - r (int): layer value
          - ctrl (dict): the edge's control vertices
  
      **Returns**
            sugiyama.DummyVertex : the created DummyVertex.
      """
      dv = DummyVertex(r)
      dv.view.w, dv.view.h = self.dw, self.dh
      self.layoutVertices[dv] = dv
      dv.control_vertices = control_vertices
      control_vertices[r] = dv
      self.layers[r].append(dv)
      return dv
  
imports: import pandas, typing
  from sys import getrecursionlimit, setrecursionlimit
  from graphistry.layout.graph import Vertex, GraphBase, Graph, Edge
  from graphistry.layout.utils import DummyVertex, LayoutVertex, Rectangle, size_median
  from graphistry.layout.utils.layer import Layer
label_desc: Use image node_id 21 for calling the SugiyamaLayout obj's underlying member method code with example usage: obj.dummyctrl(r, control_vertices) and returns: dv