input: Write a function to swap the values of two variables in Python. The function should take two variables as input and swap their values. The function should return the swapped values.
  
  def swap_variables(x, y):
      x, y = y, x
      return x, y
  
  assert swap_variables(5, 10) == (10, 5)
  assert swap_variables(20, 30) == (30, 20)
  assert swap_variables("a", "b") == ("b", "a")
  assert swap_variables(True, False) == (False, True)
  assert swap_variables([1, 2], [3, 4]) == ([3, 4], [1, 2])
output: def swap_variables(x, y):
      x, y = y, x
      return x, y