'Serialize a dict into a string and wrap in a wsgi.Request object.
:param response_data: dict produced by the Controller
:param content_type: expected mimetype of serialized response body'

def serialize(self, response_data, content_type, action='default'):

    response = webob.Response()
    self.serialize_headers(response, response_data, action)
    self.serialize_body(response, response_data, content_type, action)
    return response
