### Question:
AAIDeleteTasks { public void deleteInstanceGroup(BuildingBlockExecution execution) throws Exception { try { ServiceInstance serviceInstance = extractPojosForBB.extractByKey(execution, ResourceKey.SERVICE_INSTANCE_ID); aaiNetworkResources.deleteNetworkInstanceGroup(serviceInstance.getCollection().getInstanceGroup()); } catch (Exception ex) { logger.error("Exception occurred in AAIDeleteTasks deleteInstanceGroup process", ex); exceptionUtil.buildAndThrowWorkflowException(execution, 7000, ex); } }  void deleteVfModule(BuildingBlockExecution execution); void deleteVnf(BuildingBlockExecution execution); void deleteServiceInstance(BuildingBlockExecution execution); void deleteNetwork(BuildingBlockExecution execution); void deleteCollection(BuildingBlockExecution execution); void deleteInstanceGroup(BuildingBlockExecution execution); void deleteVolumeGroup(BuildingBlockExecution execution); void deleteConfiguration(BuildingBlockExecution execution); void deleteInstanceGroupVnf(BuildingBlockExecution execution); void deleteNetworkPolicies(BuildingBlockExecution execution);  }### Answer:
@Test public void deleteInstanceGroupTest() throws Exception { doNothing().when(aaiNetworkResources) .deleteNetworkInstanceGroup(serviceInstance.getCollection().getInstanceGroup()); aaiDeleteTasks.deleteInstanceGroup(execution); verify(aaiNetworkResources, times(1)) .deleteNetworkInstanceGroup(serviceInstance.getCollection().getInstanceGroup()); }