langchain/embeddings/aleph_alpha.py/AlephAlphaAsymmetricSemanticEmbedding/validate_environment
class AlephAlphaAsymmetricSemanticEmbedding:    def validate_environment(cls, values: Dict) -> Dict:
        """Validate that api key and python package exists in environment."""
        aleph_alpha_api_key = get_from_dict_or_env(
            values, "aleph_alpha_api_key", "ALEPH_ALPHA_API_KEY"
        )
        try:
            from aleph_alpha_client import Client
        except ImportError:
            raise ValueError(
                "Could not import aleph_alpha_client python package. "
                "Please install it with `pip install aleph_alpha_client`."
            )
        values["client"] = Client(token=aleph_alpha_api_key)
        return values