input: Write a python function to swap the values of two variables using tuple unpacking.
  ```python
  def swap(x, y):
      x, y = y, x
      return x, y
  
  # Test cases
  assert swap(1, 2) == (2, 1)
  assert swap('a', 'b') == ('b', 'a')
  assert swap(5, 10) == (10, 5)
output: def swap(x, y):
      x, y = y, x
      return x, y
  
  # Test cases
  assert swap(1, 2) == (2, 1)
  assert swap('a', 'b') == ('b', 'a')
  assert swap(5, 10) == (10, 5)