'Check Content-Type header for API version.'

def _content_type_strategy(self, host, port, environ):

    app = None
    params = parse_options_header(environ.get('CONTENT_TYPE', ''))[1]
    if ('version' in params):
        (app, app_url) = self._match(host, port, ('/v' + params['version']))
        if app:
            app = self._set_script_name(app, app_url)
    return app
