code: def add_current_vrf(self):
          
  
          vrf_id = request.json['vrf_id']
  
          if vrf_id is not None:
  
              if vrf_id == 'null':
                  vrf = VRF()
              else:
                  vrf_id = int(vrf_id)
                  vrf = VRF.get(vrf_id)
  
              session['current_vrfs'][vrf_id] = { 'id': vrf.id, 'rt': vrf.rt,
                      'name': vrf.name, 'description': vrf.description }
              session.save()
  
          return json.dumps(session.get('current_vrfs', {}))
docs: Add VRF to filter list session variable