I encountered this error when attempting to run a python3 script with the line import cv2. Seems like it is affected by my ROS kinetic installation
import cv2
ImportError: /opt/ros/kinetic/lib/python2.7/dist-packages/cv2.so: undefined symbol: PyCObject_Type
Found a simple workaround. Add this line to the top of the code
import sys
sys.path.remove('/opt/ros/kinetic/lib/python2.7/dist-packages')