code: def circular_ladder_graph(n, create_using=None):
      """Returns the circular ladder graph $CL_n$ of length n.
  
      $CL_n$ consists of two concentric n-cycles in which
      each of the n pairs of concentric nodes are joined by an edge.
  
      Node labels are the integers 0 to n-1
  
      .. plot::
  
          >>> nx.draw(nx.circular_ladder_graph(5))
  
      """
      G = ladder_graph(n, create_using)
      G.add_edge(0, n - 1)
      G.add_edge(n, 2 * n - 1)
      return G
  
imports: import itertools
  import numbers
  import networkx
  from networkx.classes import Graph
  from networkx.exception import NetworkXError
  from networkx.utils import nodes_or_number, pairwise
label_desc: Use image node_id 7 for calling a global function with example usage: circular_ladder_graph(n, create_using) and returns: G