Update README.md

Fix typo in External Use section.

README.md

@@ -49,9 +49,9 @@ from datasets import load_dataset
 from torch_geometric.data import Data
 from torch_geometric.loader import DataLoader
 
-graphs_dataset = load_dataset("graphs-datasets/ogbg-code2)
+graphs_dataset = load_dataset("graphs-datasets/ogbg-code2")
 # For the train set (replace by valid or test as needed)
-graphs_list = [Data(graph) for graph in graphs_dataset["train"]]
+graph_list = [Data(graph) for graph in graphs_dataset["train"]]
 graphs_pygeometric = DataLoader(graph_list)
 
 ```