input: Write a function to compute the sum of two input variables and store the result in a third variable. Then print the result.
  def sum_and_store(x, y):
      result = x + y
      z = result
      print(z)
  assert sum_and_store(5, 8) == None # Output: 13
output: def sum_and_store(x, y):
      result = x + y
      z = result
      print(z)