def __init__(
        self,
        *,
        credentials: Optional[str] = None,
        credentials_path: Optional[str] = None,
        model: str = "google/gemini-2.0-flash-001",
        params: Optional[InputParams] = None,
        **kwargs,
    ):
        """Initializes the VertexLLMService.

        Args:
            credentials (Optional[str]): JSON string of service account credentials.
            credentials_path (Optional[str]): Path to the service account JSON file.
            model (str): Model identifier. Defaults to "google/gemini-2.0-flash-001".
            params (InputParams): Vertex AI input parameters.
            **kwargs: Additional arguments for OpenAILLMService.
        """
        params = params or OpenAILLMService.InputParams()
        base_url = self._get_base_url(params)
        self._api_key = self._get_api_token(credentials, credentials_path)

        super().__init__(
            api_key=self._api_key, base_url=base_url, model=model, params=params, **kwargs
        )
Initializes the VertexLLMService.

        Args:
            credentials (Optional[str]): JSON string of service account credentials.
            credentials_path (Optional[str]): Path to the service account JSON file.
            model (str): Model identifier. Defaults to "google/gemini-2.0-flash-001".
            params (InputParams): Vertex AI input parameters.
            **kwargs: Additional arguments for OpenAILLMService.
        
src/pipecat/services/google/llm_vertex.py