NME calculation for 68 points

[hyperparameters]

why are you taking an average of points for eye coordinates to calculate the norm_factor

left_eye = np.average(gt_landmarks[36:42], axis=0)
right_eye = np.average(gt_landmarks[42:48], axis=0)
norm_factor = np.linalg.norm(left_eye - right_eye)

The challenge suggests the one that you have commented

# norm_factor = np.linalg.norm(gt_landmarks[36]- gt_landmarks[45])

can you please explain is this for any kind of improvements?