old_contents: if __name__ == '__main__':
      pass
  
new_contents: import pytest
  from skiski.ski import S, K, I, V
  
  
  def test_identity_operator():
      assert I(1).w() == 1
  
  
  def test_identity_skk():
      skk = S(K).dot(K).dot(1)
      i = I(1)
      assert skk.w().w() == i.w()
  
  
  def test_const_function():
      assert K(10).dot(20).w() == 10
  
  
  def test_share_function():
      a = lambda x: x * 5
      b = lambda x: x - 3
      assert S(a).dot(b).dot(5).w() == 10
  
subject: add pytest