ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all()

[xumengdi123]

opencv3
image,contours,hierarchy=cv2.findContours(thresh,cv2.RETR_TREE,cv2.CHAIN_APPROX_SIMPLE)
opencv2
contours, hierarchy = cv2.findContours(thresh,cv2.RETR_TREE,cv2.CHAIN_APPROX_SIMPLE)

so if you use opencv2, you need update distvis.py 16th row
contours = cv2.findContours(thresh, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)[0]