Update README.md

Author: arunponnusamy

README.md

@@ -15,6 +15,8 @@ When it comes to object detection, popular detection frameworks are
 
 `pip install numpy opencv-python`
 
+**Note: Python 2.x is not supported**
+
  ## YOLO (You Only Look Once)
 
  Download the pre-trained YOLO v3 weights file from this [link](https://pjreddie.com/media/files/yolov3.weights) and place it in the current directory or you can directly download to the current directory in terminal using