Returns the final WSGI response as tuple.  The first item in
        the tuple is the application iterator, the second the status and
        the third the list of headers.  The response returned is created
        specially for the given environment.  For example if the request
        method in the WSGI environment is ``'HEAD'`` the response will
        be empty and only the headers and status code will be present.

        .. versionadded:: 0.6

        :param environ: the WSGI environment of the request.
        :return: an ``(app_iter, status, headers)`` tuple.

def get_wsgi_response(self, environ):
        """Returns the final WSGI response as tuple.  The first item in
        the tuple is the application iterator, the second the status and
        the third the list of headers.  The response returned is created
        specially for the given environment.  For example if the request
        method in the WSGI environment is ``'HEAD'`` the response will
        be empty and only the headers and status code will be present.

        .. versionadded:: 0.6

        :param environ: the WSGI environment of the request.
        :return: an ``(app_iter, status, headers)`` tuple.
        """
        headers = self.get_wsgi_headers(environ)
        app_iter = self.get_app_iter(environ)
        return app_iter, self.status, headers.to_wsgi_list()