code: def phase1(self):
      # choose node pairs from (degree) weighted distribution
      rem_deg = self.remaining_degree
      while sum(rem_deg.values()) >= 2 * self.dmax**2:
          u, v = sorted(random_weighted_sample(rem_deg, 2, self.rng))
          if self.graph.has_edge(u, v):
              continue
          if self.rng.random() < self.p(u, v):  # accept edge
              self.graph.add_edge(u, v)
              self.update_remaining(u, v)
  
imports: import heapq
  import math
  from itertools import chain, combinations, zip_longest
  from operator import itemgetter
  import networkx
  from networkx.utils import py_random_state, random_weighted_sample
label_desc: Use image node_id 7 for calling the DegreeSequenceRandomGraph obj's underlying member method code with example usage: obj.phase1() without return types