input: Write a function to swap the values of two variables in Python. The function should accept two parameters and return the two variables with their values swapped.
  assert swap_values(5, 10) == (10, 5)
  assert swap_values(7, 3) == (3, 7)
  assert swap_values(0, 0) == (0, 0)
  assert swap_values(-2, 2) == (2, -2)
  assert swap_values('a', 'b') == ('b', 'a')
output: def swap_values(a, b):
      return b, a