API key to the watsonx.ai Runtime.
api_key: SecretStr | None = Field(
default_factory=(secret_from_env_multi(names_priority=['WATSONX_API_KEY', 'WATSONX_APIKEY'], deprecated={'WATSONX_APIKEY'})),
serialization_alias='api_key',
validation_alias=(AliasChoices('api_key', 'apikey')),
description='API key to the Watson Machine Learning or CPD instance.'
)