[DOC] Add docs for missing datasets (#3536)

* add missing docs

* tries fixing docs

* fixes docs

* fixes ..code
Co-authored-by: Vasilis Vryniotis <datumbox@users.noreply.github.com>

docs/source/datasets.rst

@@ -24,6 +24,18 @@ All the datasets have almost similar API. They all have two common arguments:
 
 .. currentmodule:: torchvision.datasets
 
+
+Caltech
+~~~~~~~
+
+.. autoclass:: Caltech101
+  :members: __getitem__
+  :special-members:
+
+.. autoclass:: Caltech256
+  :members: __getitem__
+  :special-members:
+
 CelebA
 ~~~~~~
 
@@ -192,6 +204,13 @@ SBU
   :members: __getitem__
   :special-members:
 
+SEMEION
+~~~~~~~
+
+.. autoclass:: SEMEION
+  :members: __getitem__
+  :special-members:
+
 STL10
 ~~~~~
 
@@ -231,3 +250,9 @@ VOC
   :members: __getitem__
   :special-members:
 
+WIDERFace
+~~~~~~~~~
+
+.. autoclass:: WIDERFace
+  :members: __getitem__
+  :special-members:

torchvision/datasets/kinetics.py

@@ -24,6 +24,7 @@ class Kinetics400(VisionDataset):
 
     Args:
         root (string): Root directory of the Kinetics-400 Dataset. Should be structured as follows:
+
             .. code::
 
                 root/

torchvision/datasets/semeion.py

@@ -8,7 +8,8 @@ from .utils import download_url, check_integrity
 
 
 class SEMEION(VisionDataset):
-    """`SEMEION <http://archive.ics.uci.edu/ml/datasets/semeion+handwritten+digit>`_ Dataset.
+    r"""`SEMEION <http://archive.ics.uci.edu/ml/datasets/semeion+handwritten+digit>`_ Dataset.
+
     Args:
         root (string): Root directory of dataset where directory
             ``semeion.py`` exists.
@@ -19,6 +20,7 @@ class SEMEION(VisionDataset):
         download (bool, optional): If true, downloads the dataset from the internet and
             puts it in root directory. If dataset is already downloaded, it is not
             downloaded again.
+
     """
     url = "http://archive.ics.uci.edu/ml/machine-learning-databases/semeion/semeion.data"
     filename = "semeion.data"
@@ -53,6 +55,7 @@ class SEMEION(VisionDataset):
         """
         Args:
             index (int): Index
+
         Returns:
             tuple: (image, target) where target is index of the target class.
         """

torchvision/datasets/widerface.py

@@ -14,6 +14,9 @@ class WIDERFace(VisionDataset):
     Args:
         root (string): Root directory where images and annotations are downloaded to.
             Expects the following folder structure if download=False:
+
+            .. code::
+
                 <root>
                     └── widerface
                         ├── wider_face_split ('wider_face_split.zip' if compressed)
@@ -29,6 +32,7 @@ class WIDERFace(VisionDataset):
         download (bool, optional): If true, downloads the dataset from the internet and
             puts it in root directory. If dataset is already downloaded, it is not
             downloaded again.
+
     """
 
     BASE_FOLDER = "widerface"