There have been many tributes to Nelson Mandela in the past week, but this supermarket flash mob is surely one of the most beautiful.Shoppers purchasing their groceries were left astounded after the Soweto Gospel Choir – many of whom posed as workers – emerged from the aisles at the Woolworths store in Johannesburg.They performed Asimbonanga (We have not seen him), a call for freedom written during Mandela’s incarceration in prison, with many onlookers moved to tears.(metro.co.uk)ANN.Az