input: Write a function to sort the given array in ascending order. If the input array is empty return an empty array. If the given array contains all the same elements like [2,2,2,2,2] then return it as is. 
  
  def sort_ascending(array):
    if not array:
      return []
    array.sort()
    return array
  
  assert sort_ascending([10, 3, 9, 1, 15, 2])==[1, 2, 3, 9, 10, 15]
  assert sort_ascending([2,2,2,2,2])==[2,2,2,2,2]
  assert sort_ascending([])==[]
output: def sort_ascending(array):
    if not array:
      return []
    array.sort()
    return array