          "signature(value, salt=...) should work"
          signer = signing.Signer('predictable-secret', salt='extra-salt')
          self.assertEqual(
              signer.signature('hello'),
                  signing.base64_hmac('extra-salt' + 'signer',
                  'hello', 'predictable-secret').decode()
          )
          self.assertNotEqual(
              signing.Signer('predictable-secret', salt='one').signature('hello'),
              signing.Signer('predictable-secret', salt='two').signature('hello'))
  
 
</s> remove                 repr(datetime.datetime.fromtimestamp(ts - 3600, tz)),
                'datetime.datetime(2010, 11, 7, 0, 0, tzinfo=EST)')
 </s> add             repr(datetime.datetime.fromtimestamp(ts - 3600, tz)),
            'datetime.datetime(2010, 11, 7, 0, 0, tzinfo=EST)') </s> remove                 repr(datetime.datetime.fromtimestamp(ts + 3600, tz)),
                'datetime.datetime(2010, 11, 7, 1, 0, tzinfo=EST)')
 </s> add             repr(datetime.datetime.fromtimestamp(ts + 3600, tz)),
            'datetime.datetime(2010, 11, 7, 1, 0, tzinfo=EST)') </s> remove                 repr(datetime.datetime.fromtimestamp(ts, tz)),
                'datetime.datetime(2010, 11, 7, 1, 0, tzinfo=EST)')
 </s> add             repr(datetime.datetime.fromtimestamp(ts, tz)),
            'datetime.datetime(2010, 11, 7, 1, 0, tzinfo=EST)') </s> remove                 InternalCertificationAudit._meta.verbose_name_plural,
                'Audits'
 </s> add             InternalCertificationAudit._meta.verbose_name_plural,
            'Audits' </s> remove                 "<Child7: barney>",
                "<Child7: fred>"
 </s> add             "<Child7: barney>",
            "<Child7: fred>"
            signing.base64_hmac('extra-salt' + 'signer',
                                'hello', 'predictable-secret').decode()
          "signature(value, salt=...) should work"
          signer = signing.Signer('predictable-secret', salt='extra-salt')
          self.assertEqual(
              signer.signature('hello'),
            signing.base64_hmac('extra-salt' + 'signer',
                                'hello', 'predictable-secret').decode()
            signing.base64_hmac('extra-salt' + 'signer',
                                'hello', 'predictable-secret').decode()
          )
          self.assertNotEqual(
              signing.Signer('predictable-secret', salt='one').signature('hello'),
              signing.Signer('predictable-secret', salt='two').signature('hello'))
  
keep keep keep keep replace replace keep keep keep keep keep
 Fixed #21288 -- Fixed E126 pep8 warnings 
tests/signing/tests.py