numpy calculates determinant for this case as -1:

numpy.linalg.det([[0,1,1],[0,2,1],[1,1,1]]) == -1

wolframalpha concludes that it is -1: https://www.wolframalpha.com/input/?i=%7B%7B0%2C1%2C1%7D%2C%7B0%2C2%2C1%7D%2C%7B1%2C1%2C1%7D%7Dhttps://www.wolframalpha.com/input/?i=%7B%7B0%2C1%2C1%7D%2C%7B0%2C2%2C1%7D%2C%7B1%2C1%2C1%7D%7D

but checker insists that Right answer: 1

Is it problem with numpy and wolframalpha, or I am doing something wrong?