Contribution #771

Problem: ru/2.7.21

Added 2.7.21 2.7.22

Editor: Aliaksandr Melnichenka ( @astrosander )

Time: December 15, 2023 at 11:16 AM

GitHub commit: 255c6796cccfb014e05d1ed486c6bac45ec2a04c

+178 -0 lines changed