python opencv errors

python2.7
>>> import cv2
[libprotobuf FATAL /home/dv1/opencv/3rdparty/protobuf/src/google/protobuf/stubs/common.cc:78] This program was compiled against version 2.6.1 of the Protocol Buffer runtime library, which is not compatible with the installed version (3.1.0).  Contact the program author for an update.  If you compiled the program yourself, make sure that your headers are from the same version of Protocol Buffers as your link-time library.  (Version verification failed in "/build/mir-O8_xaj/mir-0.26.3+16.04.20170605/obj-x86_64-linux-gnu/src/protobuf/mir_protobuf.pb.cc".)
terminate called after throwing an instance of 'google::protobuf::FatalException'
  what():  This program was compiled against version 2.6.1 of the Protocol Buffer runtime library, which is not compatible with the installed version (3.1.0).  Contact the program author for an update.  If you compiled the program yourself, make sure that your headers are from the same version of Protocol Buffers as your link-time library.  (Version verification failed in "/build/mir-O8_xaj/mir-0.26.3+16.04.20170605/obj-x86_64-linux-gnu/src/protobuf/mir_protobuf.pb.cc".)
Aborted (core dumped)



python3
    import cv2
ImportError: No module named 'cv2'