                           encode_file('IGNORE', 'IGNORE', DummyFile("file.bin"))[2])
          self.assertEqual(b'Content-Type: text/plain',
                           encode_file('IGNORE', 'IGNORE', DummyFile("file.txt"))[2])
          self.assertIn(encode_file('IGNORE', 'IGNORE', DummyFile("file.zip"))[2], (
                          b'Content-Type: application/x-compress',
                          b'Content-Type: application/x-zip',
                          b'Content-Type: application/x-zip-compressed',
                          b'Content-Type: application/zip',))
          self.assertEqual(b'Content-Type: application/octet-stream',
                           encode_file('IGNORE', 'IGNORE', DummyFile("file.unknown"))[2])
  
  class RequestHeadersTest(TestCase):
      def test_client_headers(self):
 
</s> remove                 (1, 'First'),
                (2, 'Second'),
 </s> add             (1, 'First'),
            (2, 'Second'), </s> remove         return "PK = %d, base_name = %s, derived_name = %s" \
                % (self.customPK, self.base_name, self.derived_name)
 </s> add         return "PK = %d, base_name = %s, derived_name = %s" % (
            self.customPK, self.base_name, self.derived_name) </s> remove         bool(f.rel) if hasattr(f, 'rel') else
        isinstance(f, models.related.RelatedObject)), RelatedFieldListFilter)
 </s> add     bool(f.rel) if hasattr(f, 'rel') else
    isinstance(f, models.related.RelatedObject)), RelatedFieldListFilter) </s> remove                     'django.template.loaders.filesystem.Loader',
 </s> add                 'django.template.loaders.filesystem.Loader', </s> remove             settings.AUTHENTICATION_BACKENDS) + (backend, ))
 </s> add         settings.AUTHENTICATION_BACKENDS) + (backend, ))
            b'Content-Type: application/x-compress',
            b'Content-Type: application/x-zip',
            b'Content-Type: application/x-zip-compressed',
            b'Content-Type: application/zip',))
                           encode_file('IGNORE', 'IGNORE', DummyFile("file.bin"))[2])
          self.assertEqual(b'Content-Type: text/plain',
                           encode_file('IGNORE', 'IGNORE', DummyFile("file.txt"))[2])
          self.assertIn(encode_file('IGNORE', 'IGNORE', DummyFile("file.zip"))[2], (
            b'Content-Type: application/x-compress',
            b'Content-Type: application/x-zip',
            b'Content-Type: application/x-zip-compressed',
            b'Content-Type: application/zip',))
            b'Content-Type: application/x-compress',
            b'Content-Type: application/x-zip',
            b'Content-Type: application/x-zip-compressed',
            b'Content-Type: application/zip',))
            b'Content-Type: application/x-compress',
            b'Content-Type: application/x-zip',
            b'Content-Type: application/x-zip-compressed',
            b'Content-Type: application/zip',))
            b'Content-Type: application/x-compress',
            b'Content-Type: application/x-zip',
            b'Content-Type: application/x-zip-compressed',
            b'Content-Type: application/zip',))
          self.assertEqual(b'Content-Type: application/octet-stream',
                           encode_file('IGNORE', 'IGNORE', DummyFile("file.unknown"))[2])
  
  class RequestHeadersTest(TestCase):
      def test_client_headers(self):
keep keep keep keep replace replace replace replace keep keep keep keep keep
 Fixed #21288 -- Fixed E126 pep8 warnings 
tests/test_client_regress/tests.py