langchain/llms/deepinfra.py/DeepInfra/validate_environment
class DeepInfra:    def validate_environment(cls, values: Dict) -> Dict:
        """Validate that api key and python package exists in environment."""
        deepinfra_api_token = get_from_dict_or_env(
            values, "deepinfra_api_token", "DEEPINFRA_API_TOKEN"
        )
        values["deepinfra_api_token"] = deepinfra_api_token
        return values