src/transformers/models/convbert/modeling_convbert.py/ConvBertOutput/__init__
class ConvBertOutput:    def __init__(self, config):
        super().__init__()
        if config.num_groups == 1:
            self.dense = nn.Linear(config.intermediate_size, config.hidden_size)
        else:
            self.dense = GroupedLinearLayer(
                input_size=config.intermediate_size, output_size=config.hidden_size, num_groups=config.num_groups
            )
        self.LayerNorm = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
        self.dropout = nn.Dropout(config.hidden_dropout_prob)