src/transformers/models/audio_spectrogram_transformer/modeling_audio_spectrogram_transformer.py/ASTMLPHead/__init__
class ASTMLPHead:    def __init__(self, config: ASTConfig):
        super().__init__()
        self.layernorm = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
        self.dense = nn.Linear(config.hidden_size, config.num_labels) if config.num_labels > 0 else nn.Identity()