response = requests.post(
            url=f"{base_url}/{self.model}/complete",
            headers={"Authorization": f"Bearer {self.ai21_api_key}"},
            json={"prompt": prompt, "stopSequences": stop, **params},
        )
        if response.status_code != 200:
            optional_detail = response.json().get("error")
            raise ValueError(
                f"AI21 /complete call failed with status code {response.status_code}."
                f" Details: {optional_detail}"
            )
        response_json = response.json()
        return response_json["completions"][0]["data"]["text"]