src/transformers/models/albert/modeling_albert.py/AlbertModel/__init__
class AlbertModel:    def __init__(self, config, add_pooling_layer=True):
        super().__init__(config)

        self.config = config
        self.embeddings = AlbertEmbeddings(config)
        self.encoder = AlbertTransformer(config)
        if add_pooling_layer:
            self.pooler = nn.Linear(config.hidden_size, config.hidden_size)
            self.pooler_activation = nn.Tanh()
        else:
            self.pooler = None
            self.pooler_activation = None

        self.init_weights()