how to show image via opencv using rospy ROS Kinetic

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i want to stream my camera using opencv, this is my whole code

   #!/usr/bin/env python2.7
    import rospy
    from sensor_msgs.msg import Image, CompressedImage
    import cv2
    from cv_bridge import CvBridge, CvBridgeError
    import sys

    rospy.init_node('opencv_example', anonymous=True)
    bridge = CvBridge()

    def show_image(img):
        cv2.imshow("Image Window", img)
        cv2.waitKey(3)

   def image_callback(img_msg):

    try:
        np_arr = np.fromstring(img_msg.data, np.uint8)
        image_np = cv2.imdecode(np_arr, cv2.IMREAD_COLOR)
        cv_image = bridge.imgmsg_to_cv2(img_msg, "bgr8")
    except CvBridgeError, e:
        rospy.logerr("CvBridge Error: {0}".format(e))

    show_image(cv_image)

    sub_image = rospy.Subscriber("/raspicam_node/image/compressed", CompressedImage, image_callback)
    cv2.namedWindow("Image Window", 1)

    while not rospy.is_shutdown():
          rospy.spin()

after i try to stream the compressed image from my raspicam node, all i get is this code:

  [ERROR] [1635390346.816659]: bad callback: <function image_callback at 0x7f9c224ccb18>
Traceback (most recent call last):
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/rospy/topics.py", line 750, in _invoke_callback
    cb(msg)
  File "/home/anto/catkin_ws/src/opencv_example/src/opencv_ex.py", line 22, in image_callback
    cv_image = bridge.imgmsg_to_cv2(img_msg, "bgr8")
  File "/home/anto/catkin_ws/src/vision_opencv-kinetic/cv_bridge/python/cv_bridge/core.py", line 163, in imgmsg_to_cv2
    dtype, n_channels = self.encoding_to_dtype_with_channels(img_msg.encoding)
AttributeError: 'CompressedImage' object has no attribute 'encoding'

currently, I am working with

• Ubuntu 16.04
• Ros Kinetic
• Open CV 3.3.1
• python 2.7