True, ImagePipelineOutput is returned, otherwise a tuple is
returned where the first element is a list with the generated images.
  The call function to the pipeline for generation.  UnCLIPImageVariationPipeline  class diffusers.UnCLIPImageVariationPipeline  < source > ( decoder: UNet2DConditionModel text_encoder: CLIPTextModelWithProjection tokenizer: CLIPTokenizer text_proj: UnCLIPTextProjModel feature_extractor: CLIPImageProcessor image_enco