Replace tornado.util.bytes_type to bytes

diff --git a/demos/s3server/s3server.py b/demos/s3server/s3server.py
index 87816c3288f086b533809ffda947eaf280151f08..5a4805694e2426a97867f370b07461beff808b7c 100644 (file)
--- a/demos/s3server/s3server.py
+++ b/demos/s3server/s3server.py
@@ -42,7 +42,6 @@ from tornado import escape
 from tornado import httpserver
 from tornado import ioloop
 from tornado import web
-from tornado.util import bytes_type
 
 def start(port, root_directory="/tmp/s3", bucket_depth=0):
     """Starts the mock S3 server on the given port at the given path."""
@@ -87,7 +86,7 @@ class BaseRequestHandler(web.RequestHandler):
                     ''.join(parts))
 
     def _render_parts(self, value, parts=[]):
-        if isinstance(value, (unicode, bytes_type)):
+        if isinstance(value, (unicode, bytes)):
             parts.append(escape.xhtml_escape(value))
         elif isinstance(value, int) or isinstance(value, long):
             parts.append(str(value))

diff --git a/maint/test/websocket/server.py b/maint/test/websocket/server.py
index 305bd7468038ae50ba93524a645edc4916715cde..602cc506db22bf9422f5a443045033269269fe22 100644 (file)
--- a/maint/test/websocket/server.py
+++ b/maint/test/websocket/server.py
@@ -2,7 +2,6 @@
 
 from tornado.ioloop import IOLoop
 from tornado.options import define, options, parse_command_line
-from tornado.util import bytes_type
 from tornado.websocket import WebSocketHandler
 from tornado.web import Application
 
@@ -10,7 +9,7 @@ define('port', default=9000)
 
 class EchoHandler(WebSocketHandler):
     def on_message(self, message):
-        self.write_message(message, binary=isinstance(message, bytes_type))
+        self.write_message(message, binary=isinstance(message, bytes))
 
     def get_compression_options(self):
         return {}

diff --git a/tornado/auth.py b/tornado/auth.py
index 7bd3fa1ed490975d9429320b8f5ed85d2b45d0e6..c503442a5d4e200a953717524c2ebaf8b3e9f366 100644 (file)
--- a/tornado/auth.py
+++ b/tornado/auth.py
@@ -76,7 +76,7 @@ from tornado import escape
 from tornado.httputil import url_concat
 from tornado.log import gen_log
 from tornado.stack_context import ExceptionStackContext
-from tornado.util import bytes_type, u, unicode_type, ArgReplacer
+from tornado.util import u, unicode_type, ArgReplacer
 
 try:
     import urlparse  # py2
@@ -1112,7 +1112,7 @@ class FacebookMixin(object):
             args["cancel_url"] = urlparse.urljoin(
                 self.request.full_url(), cancel_uri)
         if extended_permissions:
-            if isinstance(extended_permissions, (unicode_type, bytes_type)):
+            if isinstance(extended_permissions, (unicode_type, bytes)):
                 extended_permissions = [extended_permissions]
             args["req_perms"] = ",".join(extended_permissions)
         self.redirect("http://www.facebook.com/login.php?" +

diff --git a/tornado/curl_httpclient.py b/tornado/curl_httpclient.py
index 2ed6fcf61d19e74494ed9cfa3714315948037057..9c2aeb9f2e0c4e9d4b70522650ec234c57690bf9 100644 (file)
--- a/tornado/curl_httpclient.py
+++ b/tornado/curl_httpclient.py
@@ -32,7 +32,6 @@ from tornado import stack_context
 
 from tornado.escape import utf8, native_str
 from tornado.httpclient import HTTPResponse, HTTPError, AsyncHTTPClient, main
-from tornado.util import bytes_type
 
 
 class CurlAsyncHTTPClient(AsyncHTTPClient):
@@ -307,7 +306,7 @@ def _curl_setup_request(curl, request, buffer, headers):
         write_function = request.streaming_callback
     else:
         write_function = buffer.write
-    if bytes_type is str:  # py2
+    if bytes is str:  # py2
         curl.setopt(pycurl.WRITEFUNCTION, write_function)
     else:  # py3
         # Upstream pycurl doesn't support py3, but ubuntu 12.10 includes

diff --git a/tornado/escape.py b/tornado/escape.py
index 48fa673c107517c081aa2f59d3604f2d1748c955..24be2264ba85b54ee8efaf24c58ccafc7e6bd335 100644 (file)
--- a/tornado/escape.py
+++ b/tornado/escape.py
@@ -25,7 +25,7 @@ from __future__ import absolute_import, division, print_function, with_statement
 import re
 import sys
 
-from tornado.util import bytes_type, unicode_type, basestring_type, u
+from tornado.util import unicode_type, basestring_type, u
 
 try:
     from urllib.parse import parse_qs as _parse_qs  # py3
@@ -187,7 +187,7 @@ else:
         return encoded
 
 
-_UTF8_TYPES = (bytes_type, type(None))
+_UTF8_TYPES = (bytes, type(None))
 
 
 def utf8(value):
@@ -215,7 +215,7 @@ def to_unicode(value):
     """
     if isinstance(value, _TO_UNICODE_TYPES):
         return value
-    if not isinstance(value, bytes_type):
+    if not isinstance(value, bytes):
         raise TypeError(
             "Expected bytes, unicode, or None; got %r" % type(value)
         )
@@ -246,7 +246,7 @@ def to_basestring(value):
     """
     if isinstance(value, _BASESTRING_TYPES):
         return value
-    if not isinstance(value, bytes_type):
+    if not isinstance(value, bytes):
         raise TypeError(
             "Expected bytes, unicode, or None; got %r" % type(value)
         )
@@ -264,7 +264,7 @@ def recursive_unicode(obj):
         return list(recursive_unicode(i) for i in obj)
     elif isinstance(obj, tuple):
         return tuple(recursive_unicode(i) for i in obj)
-    elif isinstance(obj, bytes_type):
+    elif isinstance(obj, bytes):
         return to_unicode(obj)
     else:
         return obj

diff --git a/tornado/httputil.py b/tornado/httputil.py
index c472998faac056ad82458ba9aed2112ce69c7901..126db40e3b589353cb848f363a1f48a8b4718b52 100644 (file)
--- a/tornado/httputil.py
+++ b/tornado/httputil.py
@@ -33,7 +33,7 @@ import time
 
 from tornado.escape import native_str, parse_qs_bytes, utf8
 from tornado.log import gen_log
-from tornado.util import ObjectDict, bytes_type
+from tornado.util import ObjectDict
 
 try:
     import Cookie  # py2
@@ -379,7 +379,7 @@ class HTTPServerRequest(object):
            Use ``request.connection`` and the `.HTTPConnection` methods
            to write the response.
         """
-        assert isinstance(chunk, bytes_type)
+        assert isinstance(chunk, bytes)
         self.connection.write(chunk, callback=callback)
 
     def finish(self):

diff --git a/tornado/iostream.py b/tornado/iostream.py
index 3726a768e7449f2dffa3b06483dbdd48a7ddc5d2..94fbb947684af3da191cd228d1d3bf1d1fc22056 100644 (file)
--- a/tornado/iostream.py
+++ b/tornado/iostream.py
@@ -39,7 +39,7 @@ from tornado import ioloop
 from tornado.log import gen_log, app_log
 from tornado.netutil import ssl_wrap_socket, ssl_match_hostname, SSLCertificateError
 from tornado import stack_context
-from tornado.util import bytes_type, errno_from_exception
+from tornado.util import errno_from_exception
 
 try:
     from tornado.platform.posix import _set_nonblocking
@@ -324,7 +324,7 @@ class BaseIOStream(object):
         .. versionchanged:: 4.0
             Now returns a `.Future` if no callback is given.
         """
-        assert isinstance(data, bytes_type)
+        assert isinstance(data, bytes)
         self._check_closed()
         # We use bool(_write_buffer) as a proxy for write_buffer_size>0,
         # so never put empty strings in the buffer.

diff --git a/tornado/template.py b/tornado/template.py
index 4dcec5d5f617f92591f6ac503f3de14a1ee93052..3882ed02a8eef91680caf578b5aa7326906d7d18 100644 (file)
--- a/tornado/template.py
+++ b/tornado/template.py
@@ -199,7 +199,7 @@ import threading
 
 from tornado import escape
 from tornado.log import app_log
-from tornado.util import bytes_type, ObjectDict, exec_in, unicode_type
+from tornado.util import ObjectDict, exec_in, unicode_type
 
 try:
     from cStringIO import StringIO  # py2
@@ -261,7 +261,7 @@ class Template(object):
             "linkify": escape.linkify,
             "datetime": datetime,
             "_tt_utf8": escape.utf8,  # for internal use
-            "_tt_string_types": (unicode_type, bytes_type),
+            "_tt_string_types": (unicode_type, bytes),
             # __name__ and __loader__ allow the traceback mechanism to find
             # the generated source code.
             "__name__": self.name.replace('.', '_'),

diff --git a/tornado/test/escape_test.py b/tornado/test/escape_test.py
index 9abc74803aa712080726bc60cf82e541304303ad..7cc81abf27da325d9fd52b52a2b12d1db2a14778 100644 (file)
--- a/tornado/test/escape_test.py
+++ b/tornado/test/escape_test.py
@@ -5,7 +5,7 @@ from __future__ import absolute_import, division, print_function, with_statement
 import tornado.escape
 
 from tornado.escape import utf8, xhtml_escape, xhtml_unescape, url_escape, url_unescape, to_unicode, json_decode, json_encode
-from tornado.util import u, unicode_type, bytes_type
+from tornado.util import u, unicode_type
 from tornado.test.util import unittest
 
 linkify_tests = [
@@ -212,6 +212,6 @@ class EscapeTestCase(unittest.TestCase):
         # convert automatically if they are utf8; on python 3 byte strings
         # are not allowed.
         self.assertEqual(json_decode(json_encode(u("\u00e9"))), u("\u00e9"))
-        if bytes_type is str:
+        if bytes is str:
             self.assertEqual(json_decode(json_encode(utf8(u("\u00e9")))), u("\u00e9"))
             self.assertRaises(UnicodeDecodeError, json_encode, b"\xe9")

diff --git a/tornado/test/httpclient_test.py b/tornado/test/httpclient_test.py
index 104ed632c93e50b15e29d727d401e2aae726f55c..123b2cfd4d5eea4a91a14ec14b1fdffcc495aa8e 100644 (file)
--- a/tornado/test/httpclient_test.py
+++ b/tornado/test/httpclient_test.py
@@ -20,7 +20,7 @@ from tornado import netutil
 from tornado.stack_context import ExceptionStackContext, NullContext
 from tornado.testing import AsyncHTTPTestCase, bind_unused_port, gen_test, ExpectLog
 from tornado.test.util import unittest, skipOnTravis
-from tornado.util import u, bytes_type
+from tornado.util import u
 from tornado.web import Application, RequestHandler, url
 
 
@@ -287,7 +287,7 @@ Transfer-Encoding: chunked
 
     def test_types(self):
         response = self.fetch("/hello")
-        self.assertEqual(type(response.body), bytes_type)
+        self.assertEqual(type(response.body), bytes)
         self.assertEqual(type(response.headers["Content-Type"]), str)
         self.assertEqual(type(response.code), int)
         self.assertEqual(type(response.effective_url), str)

diff --git a/tornado/test/httpserver_test.py b/tornado/test/httpserver_test.py
index 5d1b780e3877329f17e3ec3d84e39aab03847094..24056338a43931ab0732a55bdefeb9c26f73561c 100644 (file)
--- a/tornado/test/httpserver_test.py
+++ b/tornado/test/httpserver_test.py
@@ -14,7 +14,7 @@ from tornado.netutil import ssl_options_to_context
 from tornado.simple_httpclient import SimpleAsyncHTTPClient
 from tornado.testing import AsyncHTTPTestCase, AsyncHTTPSTestCase, AsyncTestCase, ExpectLog, gen_test
 from tornado.test.util import unittest, skipOnTravis
-from tornado.util import u, bytes_type
+from tornado.util import u
 from tornado.web import Application, RequestHandler, asynchronous, stream_request_body
 from contextlib import closing
 import datetime
@@ -293,10 +293,10 @@ class TypeCheckHandler(RequestHandler):
         # secure cookies
 
         self.check_type('arg_key', list(self.request.arguments.keys())[0], str)
-        self.check_type('arg_value', list(self.request.arguments.values())[0][0], bytes_type)
+        self.check_type('arg_value', list(self.request.arguments.values())[0][0], bytes)
 
     def post(self):
-        self.check_type('body', self.request.body, bytes_type)
+        self.check_type('body', self.request.body, bytes)
         self.write(self.errors)
 
     def get(self):
@@ -354,7 +354,7 @@ class HTTPServerTest(AsyncHTTPTestCase):
         # if the data is not utf8.  On python 2 parse_qs will work,
         # but then the recursive_unicode call in EchoHandler will
         # fail.
-        if str is bytes_type:
+        if str is bytes:
             return
         with ExpectLog(gen_log, 'Invalid x-www-form-urlencoded body'):
             response = self.fetch(

diff --git a/tornado/test/log_test.py b/tornado/test/log_test.py
index ee832c54112332b72f845627c7d84fa6e4d75668..6fad5ca02f2b2b8f4fe3f6aad255b823c997599e 100644 (file)
--- a/tornado/test/log_test.py
+++ b/tornado/test/log_test.py
@@ -29,7 +29,7 @@ from tornado.escape import utf8
 from tornado.log import LogFormatter, define_logging_options, enable_pretty_logging
 from tornado.options import OptionParser
 from tornado.test.util import unittest
-from tornado.util import u, bytes_type, basestring_type
+from tornado.util import u, basestring_type
 
 
 @contextlib.contextmanager
@@ -96,7 +96,7 @@ class LogFormatterTest(unittest.TestCase):
 
     def test_utf8_logging(self):
         self.logger.error(u("\u00e9").encode("utf8"))
-        if issubclass(bytes_type, basestring_type):
+        if issubclass(bytes, basestring_type):
             # on python 2, utf8 byte strings (and by extension ascii byte
             # strings) are passed through as-is.
             self.assertEqual(self.get_output(), utf8(u("\u00e9")))

diff --git a/tornado/test/template_test.py b/tornado/test/template_test.py
index 6d8b624eb9405f25a00207164ff835190d73f926..ac1fbbd049df306ed7afd61380d62d87d8c5f4d1 100644 (file)
--- a/tornado/test/template_test.py
+++ b/tornado/test/template_test.py
@@ -7,7 +7,7 @@ import traceback
 from tornado.escape import utf8, native_str, to_unicode
 from tornado.template import Template, DictLoader, ParseError, Loader
 from tornado.test.util import unittest
-from tornado.util import u, bytes_type, ObjectDict, unicode_type
+from tornado.util import u, ObjectDict, unicode_type
 
 
 class TemplateTest(unittest.TestCase):
@@ -374,7 +374,7 @@ raw: {% raw name %}""",
                              "{% autoescape py_escape %}s = {{ name }}\n"})
 
         def py_escape(s):
-            self.assertEqual(type(s), bytes_type)
+            self.assertEqual(type(s), bytes)
             return repr(native_str(s))
 
         def render(template, name):

diff --git a/tornado/test/web_test.py b/tornado/test/web_test.py
index 3e7176cefb4cd1da8176de605550abc00e264f62..1ad3794cbcc4996f369e44b00d113b94f4f9b981 100644 (file)
--- a/tornado/test/web_test.py
+++ b/tornado/test/web_test.py
@@ -10,7 +10,7 @@ from tornado.simple_httpclient import SimpleAsyncHTTPClient
 from tornado.template import DictLoader
 from tornado.testing import AsyncHTTPTestCase, ExpectLog, gen_test
 from tornado.test.util import unittest
-from tornado.util import u, bytes_type, ObjectDict, unicode_type
+from tornado.util import u, ObjectDict, unicode_type
 from tornado.web import RequestHandler, authenticated, Application, asynchronous, url, HTTPError, StaticFileHandler, _create_signature_v1, create_signed_value, decode_signed_value, ErrorHandler, UIModule, MissingArgumentError, stream_request_body, Finish
 
 import binascii
@@ -302,7 +302,7 @@ class EchoHandler(RequestHandler):
             if type(key) != str:
                 raise Exception("incorrect type for key: %r" % type(key))
             for value in self.request.arguments[key]:
-                if type(value) != bytes_type:
+                if type(value) != bytes:
                     raise Exception("incorrect type for value: %r" %
                                     type(value))
             for value in self.get_arguments(key):
@@ -370,10 +370,10 @@ class TypeCheckHandler(RequestHandler):
         if list(self.cookies.keys()) != ['asdf']:
             raise Exception("unexpected values for cookie keys: %r" %
                             self.cookies.keys())
-        self.check_type('get_secure_cookie', self.get_secure_cookie('asdf'), bytes_type)
+        self.check_type('get_secure_cookie', self.get_secure_cookie('asdf'), bytes)
         self.check_type('get_cookie', self.get_cookie('asdf'), str)
 
-        self.check_type('xsrf_token', self.xsrf_token, bytes_type)
+        self.check_type('xsrf_token', self.xsrf_token, bytes)
         self.check_type('xsrf_form_html', self.xsrf_form_html(), str)
 
         self.check_type('reverse_url', self.reverse_url('typecheck', 'foo'), str)
@@ -399,7 +399,7 @@ class TypeCheckHandler(RequestHandler):
 
 class DecodeArgHandler(RequestHandler):
     def decode_argument(self, value, name=None):
-        if type(value) != bytes_type:
+        if type(value) != bytes:
             raise Exception("unexpected type for value: %r" % type(value))
         # use self.request.arguments directly to avoid recursion
         if 'encoding' in self.request.arguments:
@@ -409,7 +409,7 @@ class DecodeArgHandler(RequestHandler):
 
     def get(self, arg):
         def describe(s):
-            if type(s) == bytes_type:
+            if type(s) == bytes:
                 return ["bytes", native_str(binascii.b2a_hex(s))]
             elif type(s) == unicode_type:
                 return ["unicode", s]

diff --git a/tornado/util.py b/tornado/util.py
index b6e06c678b7aed0d8c9f2aa6fa8022306b6bf744..c86fe983ac37e3ac1ca4723350568d240c38a162 100644 (file)
--- a/tornado/util.py
+++ b/tornado/util.py
@@ -115,13 +115,11 @@ def import_object(name):
 if type('') is not type(b''):
     def u(s):
         return s
-    bytes_type = bytes
     unicode_type = str
     basestring_type = str
 else:
     def u(s):
         return s.decode('unicode_escape')
-    bytes_type = str
     unicode_type = unicode
     basestring_type = basestring
 
@@ -237,7 +235,7 @@ class Configurable(object):
         some parameters.
         """
         base = cls.configurable_base()
-        if isinstance(impl, (unicode_type, bytes_type)):
+        if isinstance(impl, (unicode_type, bytes)):
             impl = import_object(impl)
         if impl is not None and not issubclass(impl, cls):
             raise ValueError("Invalid subclass of %s" % cls)

diff --git a/tornado/web.py b/tornado/web.py
index aa7c0134abe74416f51b9698c7d9b22431783984..afc72facb888d9060e0fc3681106661d8267c8ad 100644 (file)
--- a/tornado/web.py
+++ b/tornado/web.py
@@ -84,7 +84,7 @@ from tornado.log import access_log, app_log, gen_log
 from tornado import stack_context
 from tornado import template
 from tornado.escape import utf8, _unicode
-from tornado.util import bytes_type, import_object, ObjectDict, raise_exc_info, unicode_type, _websocket_mask
+from tornado.util import import_object, ObjectDict, raise_exc_info, unicode_type, _websocket_mask
 
 
 try:
@@ -341,7 +341,7 @@ class RequestHandler(object):
     _INVALID_HEADER_CHAR_RE = re.compile(br"[\x00-\x1f]")
 
     def _convert_header_value(self, value):
-        if isinstance(value, bytes_type):
+        if isinstance(value, bytes):
             pass
         elif isinstance(value, unicode_type):
             value = value.encode('utf-8')
@@ -649,7 +649,7 @@ class RequestHandler(object):
             raise RuntimeError("Cannot write() after finish().  May be caused "
                                "by using async operations without the "
                                "@asynchronous decorator.")
-        if not isinstance(chunk, (bytes_type, unicode_type, dict)):
+        if not isinstance(chunk, (bytes, unicode_type, dict)):
             raise TypeError("write() only accepts bytes, unicode, and dict objects")
         if isinstance(chunk, dict):
             chunk = escape.json_encode(chunk)
@@ -674,7 +674,7 @@ class RequestHandler(object):
                 js_embed.append(utf8(embed_part))
             file_part = module.javascript_files()
             if file_part:
-                if isinstance(file_part, (unicode_type, bytes_type)):
+                if isinstance(file_part, (unicode_type, bytes)):
                     js_files.append(file_part)
                 else:
                     js_files.extend(file_part)
@@ -683,7 +683,7 @@ class RequestHandler(object):
                 css_embed.append(utf8(embed_part))
             file_part = module.css_files()
             if file_part:
-                if isinstance(file_part, (unicode_type, bytes_type)):
+                if isinstance(file_part, (unicode_type, bytes)):
                     css_files.append(file_part)
                 else:
                     css_files.extend(file_part)
@@ -2169,7 +2169,7 @@ class StaticFileHandler(RequestHandler):
 
         if include_body:
             content = self.get_content(self.absolute_path, start, end)
-            if isinstance(content, bytes_type):
+            if isinstance(content, bytes):
                 content = [content]
             for chunk in content:
                 self.write(chunk)
@@ -2340,7 +2340,7 @@ class StaticFileHandler(RequestHandler):
         """
         data = cls.get_content(abspath)
         hasher = hashlib.md5()
-        if isinstance(data, bytes_type):
+        if isinstance(data, bytes):
             hasher.update(data)
         else:
             for chunk in data:
@@ -2715,7 +2715,7 @@ class TemplateModule(UIModule):
     def javascript_files(self):
         result = []
         for f in self._get_resources("javascript_files"):
-            if isinstance(f, (unicode_type, bytes_type)):
+            if isinstance(f, (unicode_type, bytes)):
                 result.append(f)
             else:
                 result.extend(f)
@@ -2727,7 +2727,7 @@ class TemplateModule(UIModule):
     def css_files(self):
         result = []
         for f in self._get_resources("css_files"):
-            if isinstance(f, (unicode_type, bytes_type)):
+            if isinstance(f, (unicode_type, bytes)):
                 result.append(f)
             else:
                 result.extend(f)
@@ -2832,7 +2832,7 @@ class URLSpec(object):
             return self._path
         converted_args = []
         for a in args:
-            if not isinstance(a, (unicode_type, bytes_type)):
+            if not isinstance(a, (unicode_type, bytes)):
                 a = str(a)
             converted_args.append(escape.url_escape(utf8(a), plus=False))
         return self._path % tuple(converted_args)

diff --git a/tornado/websocket.py b/tornado/websocket.py
index f14077eddd6b85d54718e5101474e33c9eecd09b..c414f76559171cbd1d46a75fee701fdeb50e09d1 100644 (file)
--- a/tornado/websocket.py
+++ b/tornado/websocket.py
@@ -36,7 +36,7 @@ from tornado.iostream import StreamClosedError
 from tornado.log import gen_log, app_log
 from tornado import simple_httpclient
 from tornado.tcpclient import TCPClient
-from tornado.util import bytes_type, _websocket_mask
+from tornado.util import _websocket_mask
 
 try:
     from urllib.parse import urlparse # py2
@@ -651,7 +651,7 @@ class WebSocketProtocol13(WebSocketProtocol):
         else:
             opcode = 0x1
         message = tornado.escape.utf8(message)
-        assert isinstance(message, bytes_type)
+        assert isinstance(message, bytes)
         self._message_bytes_out += len(message)
         flags = 0
         if self._compressor:
@@ -664,7 +664,7 @@ class WebSocketProtocol13(WebSocketProtocol):
 
     def write_ping(self, data):
         """Send ping frame."""
-        assert isinstance(data, bytes_type)
+        assert isinstance(data, bytes)
         self._write_frame(True, 0x9, data)
 
     def _receive_frame(self):

diff --git a/tornado/wsgi.py b/tornado/wsgi.py
index 05d1e7495c45dd4dd76356a13ea6b9d4ee4c376c..f3aa66503c3bfadb1b2b0b24cbe8961c70967274 100644 (file)
--- a/tornado/wsgi.py
+++ b/tornado/wsgi.py
@@ -41,7 +41,7 @@ from tornado import httputil
 from tornado.log import access_log
 from tornado import web
 from tornado.escape import native_str
-from tornado.util import bytes_type, unicode_type
+from tornado.util import unicode_type
 
 
 try:
@@ -55,7 +55,7 @@ except ImportError:
 # here to minimize the temptation to use them in non-wsgi contexts.
 if str is unicode_type:
     def to_wsgi_str(s):
-        assert isinstance(s, bytes_type)
+        assert isinstance(s, bytes)
         return s.decode('latin1')
 
     def from_wsgi_str(s):
@@ -63,7 +63,7 @@ if str is unicode_type:
         return s.encode('latin1')
 else:
     def to_wsgi_str(s):
-        assert isinstance(s, bytes_type)
+        assert isinstance(s, bytes)
         return s
 
     def from_wsgi_str(s):