 Complete the following phrase:  In 1977 Parcham reunited with Khalq and following the Saur Revolution of 1978 many Parchamites were represented in the initial government. Very soon after the revolution, Parchamites were purged from the government by the Khalqist leadership of Nur Muhammad Taraki, and the regime eventually went into a reign of terror, jailing and executing many Parchamites. The Parcham faction seized power in the country after the toppling of Hafizullah Amin in December 1979 by the Soviet Unions 