rated tokens representing latent vectors in self.vqvae, to be used as inputs for image
gneration. If not provided, the starting latents will be completely masked.   prompt_embeds (torch.FloatTensor, optional) —
Pre-generated text embeddings. Can be used to easily tweak text inputs (prompt weighting). If not
provided, text embeddings are generated from the prompt input argument. A single vector from the
pooled and projected final hidden states. 