sponding to the second text encoder. Otherwise, it is from the first.  forward  < source > ( hidden_states: Optional = None hidden_states_1: Optional = None attention_mask: Optional = None attention_mask_1: Optional = None  )     AudioLDM2UNet2DConditionModel  class diffusers.AudioLDM2UNet2DConditionModel  < source > ( sample_size: Optional = None in_channels: int = 4 out_channels: int = 4 flip_sin_to_cos: bool = True freq_shift: int = 0 down_b