ImportError: cannot import name EXT_MSG

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Hi,I am using ubuntu14.04+indigo

I got an error when I run catkin_make

[ 67%] Built target actionlib_msgs_generate_messages_cpp
Traceback (most recent call last):
  File "/opt/ros/indigo/share/genmsg/cmake/../../../lib/genmsg/genmsg_check_deps.py", line 41, in <module>
    from genmsg import EXT_MSG, EXT_SRV, MsgContext
ImportError: cannot import name EXT_MSG
make[2]: *** [procrob_functional/CMakeFiles/_face_recognition_generate_messages_check_deps_FaceRecognitionResult] Error 1
make[1]: *** [procrob_functional/CMakeFiles/_face_recognition_generate_messages_check_deps_FaceRecognitionResult.dir/all] Error 2
make[1]: *** Waiting for unfinished jobs....
Traceback (most recent call last):
  File "/opt/ros/indigo/share/genmsg/cmake/../../../lib/genmsg/genmsg_check_deps.py", line 41, in <module>
    from genmsg import EXT_MSG, EXT_SRV, MsgContext
ImportError: cannot import name EXT_MSG
make[2]: *** [procrob_functional/CMakeFiles/_face_recognition_generate_messages_check_deps_FaceRecognitionGoal] Error 1
make[1]: *** [procrob_functional/CMakeFiles/_face_recognition_generate_messages_check_deps_FaceRecognitionGoal.dir/all] Error 2
Traceback (most recent call last):
  File "/opt/ros/indigo/share/genmsg/cmake/../../../lib/genmsg/genmsg_check_deps.py", line 41, in <module>
    from genmsg import EXT_MSG, EXT_SRV, MsgContext
ImportError: cannot import name EXT_MSG
make[2]: *** [procrob_functional/CMakeFiles/_face_recognition_generate_messages_check_deps_FaceRecognitionActionResult] Error 1
make[1]: *** [procrob_functional/CMakeFiles/_face_recognition_generate_messages_check_deps_FaceRecognitionActionResult.dir/all] Error 2
[ 67%] Built target std_msgs_generate_messages_cpp
make: *** [all] Error 2
Invoking "make -j4 -l4" failed

please help me,thx