o denoise an input.   encoder_hidden_states (torch.FloatTensor) —
The encoder hidden states with shape (batch, sequence_length, feature_dim).   class_labels (torch.Tensor, optional, defaults to None) —
Optional class labels for conditioning. Their embeddings will be summed with the timestep embeddings.
timestep_cond — (torch.Tensor, optional, defaults to None):
Conditional embeddings for timestep. If provided, the embeddings will be summed with