input: Write a function to sort an array in ascending order using the built-in sort method. If the array is empty, it should still return an empty array. 
  
  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([])==[]
output: def sort_ascending(array):
    array.sort()
    return array