diff --git a/modules/dnn/test/cityscapes_semsegm_test_enet.py b/modules/dnn/test/cityscapes_semsegm_test_enet.py
index e7e09d4ca4c8bd3f99c044eb081ee62b52d2cd64..5f0b4ba62517a5d3be7019b5be6e7cd7b1e62b6c 100644
--- a/modules/dnn/test/cityscapes_semsegm_test_enet.py
+++ b/modules/dnn/test/cityscapes_semsegm_test_enet.py
@@ -4,13 +4,11 @@ import os
 import fnmatch
 import argparse
 
-# sys.path.append('<path to opencv_build_dir/lib>')
-sys.path.append('/home/arrybn/build/opencv_w_contrib/lib')
 try:
     import cv2 as cv
 except ImportError:
-    raise ImportError('Can\'t find opencv. If you\'ve built it from sources without installation, '
-                      'uncomment the line before and insert there path to opencv_build_dir/lib dir')
+    raise ImportError('Can\'t find OpenCV Python module. If you\'ve built it from sources without installation, '
+                      'configure environemnt variable PYTHONPATH to "opencv_build_dir/lib" directory (with "python3" subdirectory if required)')
 try:
     import torch
 except ImportError:
diff --git a/modules/dnn/test/imagenet_cls_test_alexnet.py b/modules/dnn/test/imagenet_cls_test_alexnet.py
index de652040af24bf4329fbdc547550421a2e408b89..c136208d879ceca7b638b524d42949c64b1136e3 100644
--- a/modules/dnn/test/imagenet_cls_test_alexnet.py
+++ b/modules/dnn/test/imagenet_cls_test_alexnet.py
@@ -5,20 +5,16 @@ import os
 import argparse
 import time
 
-# sys.path.append('<path to git/caffe/python dir>')
-sys.path.append('/home/arrybn/git/caffe/python')
 try:
     import caffe
 except ImportError:
-    raise ImportError('Can\'t find caffe. If you\'ve built it from sources without installation, '
-                      'uncomment the line before and insert there path to git/caffe/python dir')
-# sys.path.append('<path to opencv_build_dir/lib>')
-sys.path.append('/home/arrybn/build/opencv_w_contrib/lib')
+    raise ImportError('Can\'t find Caffe Python module. If you\'ve built it from sources without installation, '
+                      'configure environemnt variable PYTHONPATH to "git/caffe/python" directory')
 try:
     import cv2 as cv
 except ImportError:
-    raise ImportError('Can\'t find opencv. If you\'ve built it from sources without installation, '
-                      'uncomment the line before and insert there path to opencv_build_dir/lib dir')
+    raise ImportError('Can\'t find OpenCV Python module. If you\'ve built it from sources without installation, '
+                      'configure environemnt variable PYTHONPATH to "opencv_build_dir/lib" directory (with "python3" subdirectory if required)')
 
 
 class DataFetch(object):
diff --git a/modules/dnn/test/imagenet_cls_test_googlenet.py b/modules/dnn/test/imagenet_cls_test_googlenet.py
index 210b740ff9aa6d001cfc712a809bb4eefdb17530..6c7305b022910df54c4f06d64e16a72e4166e4e5 100644
--- a/modules/dnn/test/imagenet_cls_test_googlenet.py
+++ b/modules/dnn/test/imagenet_cls_test_googlenet.py
@@ -3,20 +3,16 @@ import sys
 import os
 import argparse
 from imagenet_cls_test_alexnet import MeanChannelsFetch, CaffeModel, DnnCaffeModel, ClsAccEvaluation
-# sys.path.append('<path to git/caffe/python dir>')
-sys.path.append('/home/arrybn/git/caffe/python')
 try:
     import caffe
 except ImportError:
-    raise ImportError('Can\'t find caffe. If you\'ve built it from sources without installation, '
-                      'uncomment the line before and insert there path to git/caffe/python dir')
-# sys.path.append('<path to opencv_build_dir/lib>')
-sys.path.append('/home/arrybn/build/opencv_w_contrib/lib')
+    raise ImportError('Can\'t find Caffe Python module. If you\'ve built it from sources without installation, '
+                      'configure environemnt variable PYTHONPATH to "git/caffe/python" directory')
 try:
     import cv2 as cv
 except ImportError:
-    raise ImportError('Can\'t find opencv. If you\'ve built it from sources without installation, '
-                      'uncomment the line before and insert there path to opencv_build_dir/lib dir')
+    raise ImportError('Can\'t find OpenCV Python module. If you\'ve built it from sources without installation, '
+                      'configure environemnt variable PYTHONPATH to "opencv_build_dir/lib" directory (with "python3" subdirectory if required)')
 
 if __name__ == "__main__":
     parser = argparse.ArgumentParser()
diff --git a/modules/dnn/test/imagenet_cls_test_inception.py b/modules/dnn/test/imagenet_cls_test_inception.py
index dc4b1ac8466215d25c1343532813939806c1c36d..d6f0c55209ad65dff4d8adf949bbd0c52cbb9a53 100644
--- a/modules/dnn/test/imagenet_cls_test_inception.py
+++ b/modules/dnn/test/imagenet_cls_test_inception.py
@@ -5,13 +5,11 @@ import argparse
 import tensorflow as tf
 from tensorflow.python.platform import gfile
 from imagenet_cls_test_alexnet import MeanValueFetch, DnnCaffeModel, Framework, ClsAccEvaluation
-# sys.path.append('<path to opencv_build_dir/lib>')
-sys.path.append('/home/arrybn/build/opencv_w_contrib/lib')
 try:
     import cv2 as cv
 except ImportError:
-    raise ImportError('Can\'t find opencv. If you\'ve built it from sources without installation, '
-                      'uncomment the line before and insert there path to opencv_build_dir/lib dir')
+    raise ImportError('Can\'t find OpenCV Python module. If you\'ve built it from sources without installation, '
+                      'configure environemnt variable PYTHONPATH to "opencv_build_dir/lib" directory (with "python3" subdirectory if required)')
 
 # If you've got an exception "Cannot load libmkl_avx.so or libmkl_def.so" or similar, try to export next variable
 # before runnigng the script:
diff --git a/modules/dnn/test/pascal_semsegm_test_fcn.py b/modules/dnn/test/pascal_semsegm_test_fcn.py
index f7d9cd9dd3886989c594f91e5aac10e60ecf87ec..60b061ca37da68020d77b60f0e0be4fa3aee4ebd 100644
--- a/modules/dnn/test/pascal_semsegm_test_fcn.py
+++ b/modules/dnn/test/pascal_semsegm_test_fcn.py
@@ -5,12 +5,11 @@ import argparse
 import time
 
 from imagenet_cls_test_alexnet import CaffeModel, DnnCaffeModel
-sys.path.append('/home/arrybn/build/opencv_w_contrib/lib')
 try:
     import cv2 as cv
 except ImportError:
-    raise ImportError('Can\'t find opencv. If you\'ve built it from sources without installation, '
-                      'uncomment the line before and insert there path to opencv_build_dir/lib dir')
+    raise ImportError('Can\'t find OpenCV Python module. If you\'ve built it from sources without installation, '
+                      'configure environemnt variable PYTHONPATH to "opencv_build_dir/lib" directory (with "python3" subdirectory if required)')
 
 
 def get_metrics(conf_mat):