code: def enrich_internal_unqualified_edges(graph, subgraph):
      
      for u, v in itt.combinations(subgraph, 2):
          if not graph.has_edge(u, v):
              continue
  
          for k in graph[u][v]:
              if k < 0:
                  subgraph.add_edge(u, v, key=k, **graph[u][v][k])
docs: Add the missing unqualified edges between entities in the subgraph that are contained within the full graph.
  
      :param pybel.BELGraph graph: The full BEL graph
      :param pybel.BELGraph subgraph: The query BEL subgraph