text: import unittest
  
  from pads._not import Not
  
  
  class NotNotTest(unittest.TestCase):
      things = [None,3,"ABC",Not(27)]
      def testNot(self):
          for x in NotNotTest.things:
              self.assertEqual(Not(Not(x)),x)
      def testEq(self):
          for x in NotNotTest.things:
              for y in NotNotTest.things:
                  self.assertEqual(Not(x)==Not(y),x==y)
      def testHash(self):
          D = {Not(x):x for x in NotNotTest.things}
          for x in NotNotTest.things:
              self.assertEqual(D[Not(x)],x)
  