input: Write a function that sorts an array in ascending order. The input is an array, and the output is the same array sorted in ascending order.
  
  def sort_ascending(array):
    array.sort()
    return array
  
  assert sort_ascending([10, 3, 9, 1, 15, 2]) == [1, 2, 3, 9, 10, 15]
  assert sort_ascending([5, 2, 8, 4, 1, 9]) == [1, 2, 4, 5, 8, 9]
  assert sort_ascending([7, 7, 7, 7]) == [7, 7, 7, 7]
  assert sort_ascending([]) == []
  assert sort_ascending([-3, -1, -2, -4]) == [-4, -3, -2, -1]
output: def sort_ascending(array):
    array.sort()
    return array