src/transformers/models/funnel/modeling_funnel.py/FunnelClassificationHead/__init__
class FunnelClassificationHead:    def __init__(self, config, n_labels):
        super().__init__()
        self.linear_hidden = nn.Linear(config.d_model, config.d_model)
        self.dropout = nn.Dropout(config.hidden_dropout)
        self.linear_out = nn.Linear(config.d_model, n_labels)