- Update to version 4.5.3
+ tornado.curl_httpclient
* Improved debug logging on Python 3.
+ tornado.httpserver
* ``Content-Length`` and ``Transfer-Encoding`` headers are no longer
sent with 1xx or 204 responses (this was already true of 304
responses).
* Reading chunked requests no longer leaves the connection in a broken
state.
+ tornado.iostream
* Writing a `memoryview` can no longer result in "BufferError:
Existing exports of data: object cannot be re-sized".
+ tornado.options
* Duplicate option names are now detected properly whether they use
hyphens or underscores.
+ tornado.testing
* `.AsyncHTTPTestCase.fetch` now uses ``127.0.0.1`` instead of
``localhost``, improving compatibility with systems that have
partially-working ipv6 stacks.
+ tornado.web
* It is no longer allowed to send a body with 1xx or 204 responses.
+ tornado.websocket
* Requests with invalid websocket headers now get a response with
status code 400 instead of a closed connection.