'Writes the given chunk to the response stream.
.. deprecated:: 4.0
Use ``request.connection`` and the `.HTTPConnection` methods
to write the response.'

def write(self, chunk, callback=None):

    assert isinstance(chunk, bytes)
    assert self.version.startswith('HTTP/1.'), 'deprecated    interface    only    supported    in    HTTP/1.x'
    self.connection.write(chunk, callback=callback)
