ANKARA, Turkey—A Turkish court sentenced dozens of people, including former soldiers attached to the presidential guard regiment, to life imprisonment on Wednesday over their involvement in the 2016 failed coup attempt against President Recep Tayyip Erdogan’s government, the state-run Anadolu Agency reported. A total of 497 defendants had been on trial since 2017 for attempting to seize the military headquarters in Ankara, occupying the headquarters of the state broadcaster TRT, and of forcing a television broadcaster to read out a statement on behalf of the coup-plotters. The massive trial was one of hundreds of trials against suspected members of a network led by U.S.-based cleric Fethullah Gulen, whom Ankara accuses of orchestrating the failed attempt. Gulen, a former Erdogan ally, denies the accusation. The court in the outskirts of Ankara sentenced 38 defendants to life, including six who received aggravated life terms without the possibility of parole, Anadolu reported. Among …