import mmcv 
import pickle
ann_file = '/nas/shared/opendrivelab/litianyu/paradrive/data/navsim_infos/nuplan_navsim_train.pkl'
data_infos = mmcv.load(ann_file, file_format="pkl")
print('load')
data_infos = data_infos[:30]
with open('/nas/shared/opendrivelab/litianyu/paradrive/data/nuplan_navsim_tiny.pkl', 'wb') as f:
    pickle.dump(data_infos, f)