   class_labels (torch.FloatTensor, optional, defaults to None) —
Optional class labels for conditioning. Their embeddings will be summed with the timestep embeddings.   return_dict (bool, optional, defaults to True) —
Whether or not to return a UNet2DOutput instead of a plain tuple.   Returns 
UNet2DOutput or tuple
  
If return_dict is True, an UNet2DOutput is returned, otherwise a tuple is
returned where the first element is the sample tensor