assed along to the AttentionProcessor as defined under
self.processor in
diffusers.models.attention_processor.   return_dict (bool, optional, defaults to True) —
Whether or not to return a UNet2DConditionOutput instead of a plain
tuple.   Returns 
TransformerTemporalModelOutput or tuple
  
If return_dict is True, an TransformerTemporalModelOutput is
returned, otherwise a tuple where the first element is the sample tensor.
  The TransformerTempo