nums_frames = dataset['n_frames'][()]

Here use [()] to get the data. i don't understand, i haven't seen this kind of usage in python before. if anyone knows that, could you please explain the usage and scenerio?

CodePudding user response：

Since tuples are hashable, they can be used as dict keys. That includes the empty tuple:

d = {
    (): 'a'
}

print(d[()])

This outputs:

a