How many people were killed by Stalin in the great purge of the Soviet Union?

According to the World History (525 pages) edited by Shen Zhi, about 5 million people were implicated and 300,000-400,000 people were executed. Between 936 and 1939, more than half of party member, that is,1200,000 people, were arrested. Of the 1966 deputies at the17th Congress,10/08 were arrested, accounting for 56%. Of the 139 full members and alternate members of the Central Committee elected by the General Assembly, 98 were arrested and shot, accounting for 70%. Of the 17 members of the Politburo elected after the meeting, 5 were killed and 1 committed suicide. The loss of the army is even more amazing. Among the first five people who were awarded the rank of Marshal of the Red Army, three (tukhachevsky, yegorov and Brewer) were executed. 15 commanders, 13 were killed. There are always more than 40 thousand senior and middle-level officers at or above the battalion level who are persecuted. Almost all party and government leaders of ethnic minorities such as Ukraine and Kazakhstan were executed. Many scholars and writers have not been spared. Famous biologist vavilov, economists Condra Keefe and Chayanov, inventor and designer of Katyusha gun Langemark, director of the Jet Research Institute and tank designer Zaslavski were all killed. This long-lasting purge has caused immeasurable losses to the Soviet Union.