def get_package_url(cls, package, session=None, silent=False):
        response = get("{}/packages/{}".format(cls.bower_base_uri, package))
        return response.json().get("url", None)
def _cost_gp(self,x):
        """
        Predicts the time cost of evaluating the function at x.
        """
        m, _, _, _ = self.cost_model.predict_withGradients(x)
        return np.exp(m)