src/transformers/models/mpnet/modeling_mpnet.py/MPNetModel/__init__
class MPNetModel:    def __init__(self, config, add_pooling_layer=True):
        super().__init__(config)
        self.config = config

        self.embeddings = MPNetEmbeddings(config)
        self.encoder = MPNetEncoder(config)
        self.pooler = MPNetPooler(config) if add_pooling_layer else None

        self.init_weights()