python initialize dictionary with lists

dict_ = {key:[] for key in keys}

Here is what the above code is Doing:
1. We create a dictionary with the keys we want.
2. We create an empty list for each key.
3. We append the values to the lists.
4. We convert the lists to numpy arrays.
5. We convert the numpy arrays to torch tensors.
6. We create a dataset from the torch tensors.
7. We create a data loader from the dataset.