code: def _edges_from_permutation(self, feature_pathway_dict):
          
          network_edges = {}
          for feature, pathway_list in feature_pathway_dict.items():
              for i in range(len(pathway_list)):
                  for j in range(i + 1, len(pathway_list)):
                      vertex_i = pathway_list[i]
                      vertex_j = pathway_list[j]
                      new_edge = self.edge_tuple(vertex_i, vertex_j)
                      if new_edge not in network_edges:
                          network_edges[new_edge] = []
                      network_edges[new_edge].append(feature)
          self._augment_network(network_edges)
docs: Given a dictionary mapping each feature to the pathways
          overrepresented in the feature, build a CoNetwork by
          creating edges for every pairwise combination of pathways in a feature.