Calls the API to create an embedding for the text passed in.

model Which model to call, as a string or a types.Model.
text Free-form input text given to the model. Given a string, the model will generate an embedding based on the input text.
client If you're not relying on a default client, you pass a glm.TextServiceClient instead.
request_options Options for the request.

Dictionary containing the embedding (list of float values) for the input text.