GapiSheetsV4Model.UpdateSlicerSpecRequestSourcetype t = {slicerId : int;The id of the slicer to update.
*)spec : SlicerSpec.t;The specification to apply to the slicer.
*)fields : string;The fields that should be updated. At least one field must be specified. The root `SlicerSpec` is implied and should not be specified. A single "*"` can be used as short-hand for listing every field.
*)}