To create your own dataset from the data container.
from torch_geometric.data import Data, DataLoader

loader = DataLoader([data], batch_size=32)

The input to the DataLoader will be list. 
if you have more that one data container:

data_list = [Data(...), ..., Data(...)]
loader = DataLoader(data_list, batch_size=32)

https://pytorch-geometric.readthedocs.io/en/latest/notes/create_dataset.html