Here is the code.
class EncoderBiLSTM(nn.Module):
    def __init__(self, hidden_size, pretrained_embeddings):
        super().__init__()
        
        self.hidden_size = hidden_size
        self.embedding_dim = pretrained_embeddings.shape[1]
        self.vocab_size = pretrained_embeddings.shape[0]
        self.num_layers = 2
        self.dropout = 0.1 if self.num_layers > 1 else 0
        self.bidirectional = True
        

        self.embedding = nn.Embedding(self.vocab_size, self.embedding_dim)
        self.embedding.weight.data.copy_(torch.from_numpy(pretrained_embeddings))
        self.embedding.weight.requires_grad = False  # 冻结，无需训练
        
        self.lstm = nn.LSTM(self.embedding_dim, 
                            self.hidden_size,
                            batch_first = True,
                            dropout = self.dropout,
                            bidirectional = self.bidirectional)

        identity_init = torch.eye(self.hidden_size)
        '''
        here will report wrong.
        AttributeError: 'LSTM' object has no attribute 'weight_hh_l1'
        '''
        self.lstm.weight_hh_l0.data.copy_(torch.cat([identity_init]*4, dim=0))
        self.lstm.weight_hh_l1.data.copy_(torch.cat([identity_init]*4, dim=0))
        self.lstm.weight_hh_l0_reverse.data.copy_(torch.cat([identity_init]*4, dim=0))
        self.lstm.weight_hh_l1_reverse.data.copy_(torch.cat([identity_init]*4, dim=0))
...

lstm =nn.LSTM(...)
print(lstm.state_dict())

I have print the LSTM object’s state_dict()，‘weight_hh_l0’ is exactly there.
Is anyone coudl help me?