Returns the offer object with the given object ID.
||The unique identifier for an object. This ID must be unique across all objects from an issuer. This value should follow the format issuer ID.identifier where the former is issued by Google and latter is chosen by you. The unique identifier should only include alphanumeric characters, '.', '_', or '-'.|
This request requires authorization with the following scope (read more about authentication and authorization).
Do not supply a request body with this method.
If successful, this method returns an Offerobject resource in the response body.