If you plan to stay in Shanghai for only 3 days, you can take advantage of a 72-hour visa-free transit. A prerequisite for this is the availability of a return air ticket for a direct flight to Russia. Be sure to notify the airline's employees upon check-in to Shanghai that you are planning to request a 72-hour visa-free transit.

I remind you that this regime obliges you to fly and fly from one airport, and also to register during the first 24 hours of your stay in the hotel of Shanghai.