input: Write a function that sorts an array in ascending order using Python's built-in sort method. The function should take an array as input and return the sorted array.
  assert sort_ascending([10, 3, 9, 1, 15, 2])==[1, 2, 3, 9, 10, 15]
  assert sort_ascending([7, 4, 6, 1, 3])==[1, 3, 4, 6, 7]
  assert sort_ascending([5, 2, 8, 2, 9, 1])==[1, 2, 2, 5, 8, 9]
  assert sort_ascending([])==[]
  assert sort_ascending([1])==[1]
output: def sort_ascending(arr):
      return sorted(arr)