src/transformers/models/bigbird_pegasus/modeling_bigbird_pegasus.py/BigBirdPegasusModel/__init__
class BigBirdPegasusModel:    def __init__(self, config: BigBirdPegasusConfig):
        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 = BigBirdPegasusEncoder(config, self.shared)
        self.decoder = BigBirdPegasusDecoder(config, self.shared)

        self.init_weights()