Problems encountered while running code

### RouteNet-Erlang-main/Scheduling/Delay/check_predictions.py:
problem:
1、model.load_weights('./ckpt_dir/{}'.format(best))
Exception has occurred: ValueError
Unable to load weights saved in HDF5 format into a subclassed Model which has not created its variables yet. Call the Model first, then load the weights.
2、I can't find the following dataset
ds_test = input_fn('../../data/gnnet_data_set_evaluation_delays', label='PktsDrop', shuffle=False)
3、Why under this directory（data)
sys.path.insert(1, '../../data/')