The response object that is used by default in Flask. Works like the
response object from Werkzeug but is set to have an HTML mimetype by
default. Quite often you don't have to create this object yourself because
:meth:`~flask.Flask.make_response` will take care of that for you.
If you want to replace the response object used you can subclass this and
set :attr:`~flask.Flask.response_class` to your subclass.
.. versionchanged:: 1.0
JSON support is added to the response, like the request. This is useful
when testing to get the test client response data as JSON.
.. versionchanged:: 1.0
Added :attr:`max_cookie_size`.