- return [1, sample_element[0], sample_element[1], sample_element[0] * sample_element[0], sample_element[0] * sample_element[1], sample_element[1] * sample_element[1]]
+ return [1, sample_element[0], sample_element[1], sample_element[0]**2,
+ sample_element[0] * sample_element[1], sample_element[1]**2]