docs: def _add_disease_associations(self, disease_associations: dict) -> None:
          """Add disease association annotation to the network.
  
          :param disease_associations: Dictionary of disease-gene associations.
          """
          if disease_associations is not None:
              for target_id, disease_id_list in disease_associations.items():
                  if target_id in self.graph.vs["name"]:
                      self.graph.vs.find(name=target_id)["associated_diseases"] = disease_id_list