transfer-tune using mlp throwing NoneType error

[xintin]

Command (from tutorial): python3 tune_network.py --network resnet_50 --n-trials 100 --cost-model mlp-no-update --load-model mlp.pkl --transfer-tune

Error:

Traceback (most recent call last):
  File "tune_network.py", line 180, in <module>
    args.result_file, args.transfer_tune, args.search_type)
  File "tune_network.py", line 93, in tune_and_evaluate
    tuner.transfer_tune(tuning_opt, search_policy=policy)
  File "<pwd>/tenset/python/tvm/auto_scheduler/task_scheduler.py", line 574, in transfer_tune
    few_shot_learning='plus_mix_task'
  File "<pwd>/tenset/python/tvm/auto_scheduler/task_scheduler.py", line 121, in make_search_policies
    cost_model.model.fit_local(local_dataset)
  File "<pwd>/tenset/python/tvm/auto_scheduler/cost_model/mlp_model.py", line 464, in fit_local
    self.local_model[task] = diff_model
TypeError: 'NoneType' object does not support item assignment