load train_data error

[TongfangZhou]

when I'm trying to load the train and val data, there is an error popped out like:
unhashable type: 'dict'

The complete error message lookes like this.

 49             name_dict = {"1": 1,"2": 2,"3": 3}
 50             #key = tuple(name_dict)

---> 51 num_ids = [name_dict[a] for a in types]
52
53 # num_ids = [int(n['Event']) for n in objects]

TypeError: unhashable type: 'dict'

can you help to have a look one what's going on? thanks a lot