src/transformers/models/mbart/modeling_mbart.py/MBartModel/__init__
class MBartModel:    def __init__(self, config: MBartConfig):
        super().__init__(config)

        padding_idx, vocab_size = config.pad_token_id, config.vocab_size
        self.shared = nn.Embedding(vocab_size, config.d_model, padding_idx)

        self.encoder = MBartEncoder(config, self.shared)
        self.decoder = MBartDecoder(config, self.shared)

        self.init_weights()