feat: add tox Dataset.

torchex/data/datasets/graph/tox21.py

@@ -0,0 +1,16 @@
+from pathlib import Path
+
+from ..utils import download
+
+class Tox21Dataset(object):
+    def __init__(self, root_path='~/.torchex_data/tox21', datatype='train'):
+        self.root_path = Path(root_path).expanduser().resolve()
+        self.datatype = datatype
+
+        assert datatype in ['train', 'val', 'test'], \
+            'datatype must be [train, val, test]. ({})'.format(datatype)
+        download('https://tripod.nih.gov/tox21/challenge/download?', self.root_path)
+
+
+if __name__ == '__main__':
+    d = Tox21Dataset()

torchex/data/datasets/utils.py

@@ -0,0 +1,6 @@
+
+import requests
+
+def download(url, root_path):
+    requests.urlretrieve(url, root_path)
+    pass