code: def infer_num_vertices(architecture):
      """
      Infer number of vertices from an architecture dict.
  
      Parameters
      ----------
      architecture : dict
          Architecture in NNI format.
  
      Returns
      -------
      int
          Number of vertices.
      """
      op_keys = set(
          [k for k in architecture.keys() if k.startswith("op")]
      )
      intermediate_vertices = len(op_keys)
      assert op_keys == {
          "op{}".format(i) for i in range(1, intermediate_vertices + 1)
      }
      return intermediate_vertices + 2
  
file_path: nni/nni/nas/benchmark/nasbench101/graph_util.py
imports: import hashlib
  import numpy
  from .constants import INPUT, LABEL2ID, OUTPUT
label_desc: Use image node_id 4 for calling a global function with example usage: infer_num_vertices(architecture) and returns: unknown