def _DecoderParams(self):
    p = decoder.TransformerDecoder.Params()
    p.name = 'decoder'
    p.random_seed = 1234
    p.source_dim = 4
    p.model_dim = 4
    p.token_emb.embedding_dim = 4
    p.token_emb.max_num_shards = 1
    p.token_emb.params_init = py_utils.WeightInit.GaussianSqrtDim(
        seed=p.random_seed)
    p.position_emb.embedding_dim = 4
    p.trans_tpl.source_dim = 4
    p.trans_tpl.tr_atten_tpl.source_dim = 4
    p.trans_tpl.tr_atten_tpl.num_attention_heads = 2
    p.trans_tpl.tr_fflayer_tpl.input_dim = 4
    p.trans_tpl.tr_fflayer_tpl.hidden_dim = 8
    p.softmax.num_shards = 1
    p.target_seq_len = 5
    return p