input: Write a python function to sort an array of strings alphabetically.
  assert sort_strings(["Python", "Java", "C++"])==["C++", "Java", "Python"]
  assert sort_strings(["Banana", "Apple", "Cherry"])==["Apple", "Banana", "Cherry"]
  assert sort_strings(["dog", "cat", "elephant"])==["cat", "dog", "elephant"]
output: def sort_strings(arr):
      return sorted(arr)