code: def degree_correlation(creation_sequence):
      """
      Return the degree-degree correlation over all edges.
      """
      cs = creation_sequence
      s1 = 0  # deg_i*deg_j
      s2 = 0  # deg_i^2+deg_j^2
      s3 = 0  # deg_i+deg_j
      m = 0  # number of edges
      rd = cs.count("d")  # number of d nodes to the right
      rdi = [
          i for i, sym in enumerate(cs) if sym == "d"
      ]  # index of "d"s
      ds = degree_sequence(cs)
      for i, sym in enumerate(cs):
          if sym == "d":
              if i != rdi[0]:
                  print("Logic error in degree_correlation", i, rdi)
                  raise ValueError
              rdi.pop(0)
          degi = ds[i]
          for dj in rdi:
              degj = ds[dj]
              s1 += degj * degi
              s2 += degi**2 + degj**2
              s3 += degi + degj
              m += 1
      denom = 2 * m * s2 - s3 * s3
      numer = 4 * m * s1 - s3 * s3
      if denom == 0:
          if numer == 0:
              return 1
          raise ValueError(f"Zero Denominator but Numerator is {numer}")
      return numer / denom
  
imports: from math import sqrt
  import networkx
  from networkx.utils import py_random_state
label_desc: Use image node_id 17 for calling a global function with example usage: degree_correlation(creation_sequence) and returns: unknown, int