input: Write a python function to sort a list in descending order.
  assert descending_sort([2, 4, 3, 6, 1, 7]) == [7, 6, 4, 3, 2, 1]
  assert descending_sort([10, 5, 8, 3]) == [10, 8, 5, 3]
  assert descending_sort([1, 2, 3, 4, 5]) == [5, 4, 3, 2, 1]
output: def descending_sort(lst):
      return sorted(lst, reverse=True)