About this 3D model

This is a amazing puzzle that is inspired by one of my toys from my childhood. There are 10 balls in each face with same colour and when the middle part is rotated, 2 balls are replaced each time in the same face. The aim of this puzzle is to mix the balls and try to gather the same ones by rotating the middle part. It is a little bit challenging that there are 40 balls in total but I enjoy playing with it. Just be calm and try to solve it. Good luck !....