new_contents: import unittest
  
  
  def fact(n):
      if n < 2:
          return 1
      else:
          return n * fact(n - 1)
  
  
  class FactorialTest(unittest.TestCase):
     # def testFactZeroIsZero(self):
     #     self.assertEqual(1, fact(0))
  
     # def testFactOneIsOne(self):
     #     self.assertEqual(1, fact(1))
  
     # def testFactTwoIsTwo(self):
     #     self.assertEqual(2, fact(2))
  
     # def testFactThreeIsSix(self):
     #     self.assertEqual(6, fact(3))
  
     # def testFactFourIs24(self):
     #     self.assertEqual(24, fact(4))
  
      def testFactorial(self):
          di = {0:1, 1:1, 2:2, 3:6, 4:24}
          for key in di:
              expect = di[key]
              self.assertEqual(expect, fact(key))
  
  
  if __name__ == "__main__":
      unittest.main()
  
subject: add unittest with factorial