diff --git a/pl_bolts/datamodules/__init__.py b/pl_bolts/datamodules/__init__.py
index dd2d0423f4..5be8e03d1c 100644
--- a/pl_bolts/datamodules/__init__.py
+++ b/pl_bolts/datamodules/__init__.py
@@ -1,29 +1,98 @@
 from pl_bolts.datamodules.async_dataloader import AsynchronousLoader
 
+__all__ = []
+
 try:
     from pl_bolts.datamodules.binary_mnist_datamodule import BinaryMNISTDataModule
+except ModuleNotFoundError:
+    pass
+else:
+    __all__ += ['BinaryMNISTDataModule']
+
+try:
     from pl_bolts.datamodules.cifar10_datamodule import (
         CIFAR10DataModule,
         TinyCIFAR10DataModule,
     )
+except ModuleNotFoundError:
+    pass
+else:
+    __all__ += ['CIFAR10DataModule', 'TinyCIFAR10DataModule']
+
+try:
     from pl_bolts.datamodules.experience_source import (
         ExperienceSourceDataset,
         ExperienceSource,
         DiscountedExperienceSource,
     )
+except ModuleNotFoundError:
+    pass
+else:
+    __all__ += ['ExperienceSourceDataset', 'ExperienceSource', 'DiscountedExperienceSource']
+
+try:
     from pl_bolts.datamodules.fashion_mnist_datamodule import FashionMNISTDataModule
+except ModuleNotFoundError:
+    pass
+else:
+    __all__ += ['FashionMNISTDataModule']
+
+try:
     from pl_bolts.datamodules.imagenet_datamodule import ImagenetDataModule
+except ModuleNotFoundError:
+    pass
+else:
+    __all__ += ['ImagenetDataModule']
+
+try:
     from pl_bolts.datamodules.mnist_datamodule import MNISTDataModule
+except ModuleNotFoundError:
+    pass
+else:
+    __all__ += ['MNISTDataModule']
+
+try:
     from pl_bolts.datamodules.sklearn_datamodule import (
         SklearnDataset,
         SklearnDataModule,
         TensorDataset,
     )
+except ModuleNotFoundError:
+    pass
+else:
+    __all__ += ['SklearnDataset', 'SklearnDataModule', 'TensorDataset']
+
+try:
     from pl_bolts.datamodules.ssl_imagenet_datamodule import SSLImagenetDataModule
+except ModuleNotFoundError:
+    pass
+else:
+    __all__ += ['SSLImagenetDataModule']
+
+try:
     from pl_bolts.datamodules.stl10_datamodule import STL10DataModule
+except ModuleNotFoundError:
+    pass
+else:
+    __all__ += ['STL10DataModule']
+
+try:
     from pl_bolts.datamodules.vocdetection_datamodule import VOCDetectionDataModule
+except ModuleNotFoundError:
+    pass
+else:
+    __all__ += ['VOCDetectionDataModule']
 
+try:
     from pl_bolts.datasets.kitti_dataset import KittiDataset
+except ModuleNotFoundError:
+    pass
+else:
+    __all__ += ['KittiDataset']
+
+try:
     from pl_bolts.datamodules.kitti_datamodule import KittiDataModule
 except ModuleNotFoundError:
     pass
+else:
+    __all__ += ['KittiDataModule']
\ No newline at end of file
diff --git a/pl_bolts/datamodules/imagenet_datamodule.py b/pl_bolts/datamodules/imagenet_datamodule.py
index 588c57e46a..5ead1d40e9 100644
--- a/pl_bolts/datamodules/imagenet_datamodule.py
+++ b/pl_bolts/datamodules/imagenet_datamodule.py
@@ -9,6 +9,14 @@
 
 try:
     from torchvision import transforms as transform_lib
+except ModuleNotFoundError:
+    warn('You want to use `torchvision` which is not installed yet,'  # pragma: no-cover
+         ' install it with `pip install torchvision`.')
+    _TORCHVISION_AVAILABLE = False
+else:
+    _TORCHVISION_AVAILABLE = True
+
+try:
     from pl_bolts.datasets.imagenet_dataset import UnlabeledImagenet
 except ModuleNotFoundError:
     warn('You want to use `torchvision` which is not installed yet,'  # pragma: no-cover
diff --git a/pl_bolts/datamodules/sklearn_datamodule.py b/pl_bolts/datamodules/sklearn_datamodule.py
index 81eda9649d..4415a3e769 100644
--- a/pl_bolts/datamodules/sklearn_datamodule.py
+++ b/pl_bolts/datamodules/sklearn_datamodule.py
@@ -1,6 +1,5 @@
 import math
 from typing import Any
-from warnings import warn
 
 import numpy as np
 import torch
@@ -10,8 +9,8 @@
 try:
     from sklearn.utils import shuffle as sk_shuffle
 except ModuleNotFoundError:
-    warn('You want to use `sklearn` which is not installed yet,'  # pragma: no-cover
-         ' install it with `pip install sklearn`.')
+    raise ModuleNotFoundError('You want to use `sklearn` which is not installed yet,'  # pragma: no-cover
+                              ' install it with `pip install sklearn`.')
     _SKLEARN_AVAILABLE = False
 else:
     _SKLEARN_AVAILABLE = True
diff --git a/pl_bolts/datasets/__init__.py b/pl_bolts/datasets/__init__.py
index e2d319ce2f..85e0a2aebf 100644
--- a/pl_bolts/datasets/__init__.py
+++ b/pl_bolts/datasets/__init__.py
@@ -5,3 +5,11 @@
     DummyDataset,
     DummyDetectionDataset
 )
+
+__all__ = [
+    "RandomDictStringDataset",
+    "RandomDictDataset",
+    "RandomDataset",
+    "DummyDataset",
+    "DummyDetectionDataset",
+]
\ No newline at end of file
diff --git a/pl_bolts/datasets/imagenet_dataset.py b/pl_bolts/datasets/imagenet_dataset.py
index 4ced304764..3bf1553fd2 100644
--- a/pl_bolts/datasets/imagenet_dataset.py
+++ b/pl_bolts/datasets/imagenet_dataset.py
@@ -1,24 +1,16 @@
 import gzip
 import hashlib
-import importlib
 import os
 import shutil
 import tarfile
 import tempfile
 import zipfile
 from contextlib import contextmanager
-from warnings import warn
 
+import numpy as np
 import torch
 from torch._six import PY3
 
-_SKLEARN_AVAILABLE = importlib.util.find_spec("sklearn") is not None
-if _SKLEARN_AVAILABLE:
-    from sklearn.utils import shuffle as sk_shuffle
-else:
-    warn('You want to use `sklearn` which is not installed yet,'  # pragma: no-cover
-         ' install it with `pip install sklearn`.')
-
 try:
     from torchvision.datasets import ImageNet
     from torchvision.datasets.imagenet import load_meta_file
@@ -74,13 +66,9 @@ def __init__(
         super(ImageNet, self).__init__(self.split_folder, **kwargs)
         self.root = root
 
-        if not _SKLEARN_AVAILABLE:
-            raise ModuleNotFoundError(  # pragma: no-cover
-                'You want to use `shuffle` function from `scikit-learn` which is not installed yet.'
-            )
-
         # shuffle images first
-        self.imgs = sk_shuffle(self.imgs, random_state=1234)
+
+        shuffle(self.imgs, random_state=1234)
 
         # partition train set into [train, val]
         if split == 'train':
@@ -105,7 +93,9 @@ def __init__(
         # limit the number of classes
         if num_classes != -1:
             # choose the classes at random (but deterministic)
-            ok_classes = sk_shuffle(list(range(num_classes)), random_state=1234)
+            ok_classes = list(range(num_classes))
+            np.random.seed(1234)
+            np.random.shuffle(ok_classes)
             ok_classes = ok_classes[:num_classes]
             ok_classes = set(ok_classes)
 
@@ -117,7 +107,8 @@ def __init__(
             self.imgs = clean_imgs
 
         # shuffle again for final exit
-        self.imgs = sk_shuffle(self.imgs, random_state=1234)
+        np.random.seed(1234)
+        np.random.shuffle(self.imgs)
 
         # list of class_nbs for each image
         idcs = [idx for _, idx in self.imgs]
diff --git a/pl_bolts/datasets/ssl_amdim_datasets.py b/pl_bolts/datasets/ssl_amdim_datasets.py
index f7949a072a..33915564a4 100644
--- a/pl_bolts/datasets/ssl_amdim_datasets.py
+++ b/pl_bolts/datasets/ssl_amdim_datasets.py
@@ -1,17 +1,9 @@
 from abc import ABC
-import importlib
 from typing import Callable, Optional
 from warnings import warn
 
 import numpy as np
 
-_SKLEARN_AVAILABLE = importlib.util.find_spec("sklearn") is not None
-if _SKLEARN_AVAILABLE:
-    from sklearn.utils import shuffle as sk_shuffle
-else:
-    warn('You want to use `sklearn` which is not installed yet,'  # pragma: no-cover
-         ' install it with `pip install sklearn`.')
-
 try:
     from torchvision.datasets import CIFAR10
 except ModuleNotFoundError:
@@ -83,14 +75,11 @@ def select_nb_imgs_per_class(cls, examples, labels, nb_imgs_in_val):
 
     @classmethod
     def deterministic_shuffle(cls, x, y):
-        if not _SKLEARN_AVAILABLE:
-            raise ModuleNotFoundError(  # pragma: no-cover
-                'You want to use `shuffle` function from `scikit-learn` which is not installed yet.'
-            )
 
         n = len(x)
         idxs = list(range(0, n))
-        idxs = sk_shuffle(idxs, random_state=1234)
+        np.random.seed(1234)
+        np.random.shuffle(idxs)
 
         x = x[idxs]
 
diff --git a/pl_bolts/models/__init__.py b/pl_bolts/models/__init__.py
index 9af35d37c5..d5da4da3a1 100644
--- a/pl_bolts/models/__init__.py
+++ b/pl_bolts/models/__init__.py
@@ -7,6 +7,6 @@
 from pl_bolts.models.mnist_module import LitMNIST
 from pl_bolts.models.regression import LinearRegression, LogisticRegression
 from pl_bolts.models.vision import PixelCNN
-from pl_bolts.models.vision import UNet
 from pl_bolts.models.vision import SemSegment
+from pl_bolts.models.vision import UNet
 from pl_bolts.models.vision.image_gpt.igpt_module import GPT2, ImageGPT
diff --git a/pl_bolts/models/vision/__init__.py b/pl_bolts/models/vision/__init__.py
index e3fa295684..6b55902037 100644
--- a/pl_bolts/models/vision/__init__.py
+++ b/pl_bolts/models/vision/__init__.py
@@ -1,3 +1,3 @@
 from pl_bolts.models.vision.pixel_cnn import PixelCNN
-from pl_bolts.models.vision.unet import UNet
 from pl_bolts.models.vision.segmentation import SemSegment
+from pl_bolts.models.vision.unet import UNet
diff --git a/pl_bolts/models/vision/segmentation.py b/pl_bolts/models/vision/segmentation.py
index bc130be3a9..d44c632356 100644
--- a/pl_bolts/models/vision/segmentation.py
+++ b/pl_bolts/models/vision/segmentation.py
@@ -1,4 +1,4 @@
-from argparse import ArgumentParser, Namespace
+from argparse import ArgumentParser
 
 import pytorch_lightning as pl
 import torch