Get a list of available providers, either in total or for a specific model.Arguments:
model - If specified, returns the list of providers supporting this model.
api_key - If specified, unify API key to be used. Defaults
Returns:A list of provider names associated with the model if successful, otherwise an
empty list.
Raises:
BadRequestError: If there was an HTTP error.
ValueError: If there was an error parsing the JSON response.
BadRequestError - If there was an HTTP error.
ValueError - If there was an error parsing the JSON response.