diff --git a/examples/graphproppred/mol/main_pyg.py b/examples/graphproppred/mol/main_pyg.py
index d8b57006..1e02f5a6 100644
--- a/examples/graphproppred/mol/main_pyg.py
+++ b/examples/graphproppred/mol/main_pyg.py
@@ -10,8 +10,6 @@
 import numpy as np
 
 ### importing OGB
-
-### for loading dataset and evaluator
 from ogb.graphproppred import PygGraphPropPredDataset, Evaluator
 
 cls_criterion = torch.nn.BCEWithLogitsLoss()
@@ -164,4 +162,4 @@ def main():
 
 
 if __name__ == "__main__":
-    main()
\ No newline at end of file
+    main()
diff --git a/examples/graphproppred/ppi/main_pyg.py b/examples/graphproppred/ppi/main_pyg.py
index 52cada62..76720f80 100644
--- a/examples/graphproppred/ppi/main_pyg.py
+++ b/examples/graphproppred/ppi/main_pyg.py
@@ -10,8 +10,6 @@
 import numpy as np
 
 ### importing OGB
-
-### for loading dataset and evaluator
 from ogb.graphproppred import PygGraphPropPredDataset, Evaluator
 
 multicls_criterion = torch.nn.CrossEntropyLoss()
@@ -147,4 +145,4 @@ def main():
 
 
 if __name__ == "__main__":
-    main()
\ No newline at end of file
+    main()
diff --git a/ogb/graphproppred/__init__.py b/ogb/graphproppred/__init__.py
index 8e66896c..db0b58f7 100644
--- a/ogb/graphproppred/__init__.py
+++ b/ogb/graphproppred/__init__.py
@@ -8,5 +8,6 @@
 
 try:
     from .dataset_dgl import DglGraphPropPredDataset
+    from .dataset_dgl import collate_dgl
 except ImportError:
     pass