Belgrade theatre, CoventrySiana Bangura's play follows three west African women in Coventry who are cajoled into the water " and find themselves surfacing from grief They say water has the power to heal. So, in Siana Bangura's new play, three west African women dealing with grief and change turn up to their local pool in Coventry for weekly swimming classes. Ama has convinced her two friends from church, Blessing and…