add accum_loss for api

docs/api/api_python/transformer/mindspore.nn.transformer.Transformer.rst

@@ -40,8 +40,9 @@
 
     **输出：**
 
-    Tuple，表示包含(`output`, `encoder_layer_present`, `encoder_layer_present`)的元组。
+    Tuple，表示包含(`output`, `encoder_layer_present`, `encoder_layer_present`, `accum_loss`)的元组。
 
     - **output** (Tensor) - 如果只有编码器，则表示编码器层的输出logit。shape为[batch, src_seq_length, hidden_size] or [batch * src_seq_length, hidden_size]。如果有编码器和解码器，则输出来自于解码器层。shape为[batch, tgt_seq_length, hidden_size]或[batch * tgt_seq_length, hidden_size]。
     - **encoder_layer_present** (Tuple) - 大小为num_layers的元组，其中每个元组都是shape为((batch_size, num_heads, size_per_head, src_seq_length)或(batch_size, num_heads, src_seq_length, size_per_head))的自注意力中的投影key向量和value向量的tensor的元组。
     - **decoder_layer_present** (Tuple) - 大小为num_layers的元组，其中每个元组都是shape为((batch_size, num_heads, size_per_head, tgt_seq_length)或(batch_size, num_heads, tgt_seq_length, size_per_head))的self attention中的投影key向量和value向量的tensor的元组，或者是shape为(batch_size, num_heads, size_per_head, src_seq_length)或(batch_size, num_heads, src_seq_length, size_per_head))的交叉注意力中的投影key向量和value向量的tensor的元组。如果未设置解码器，返回值将为None。
+    - **accum_loss** (Tensor) - 表示一个辅助损失来最小化路由到每个专家的数据部分的均方，且仅仅在专家数大于1时才会返回。

mindspore/python/mindspore/nn/transformer/transformer.py

@@ -2335,7 +2335,7 @@ class Transformer(Cell):
               Used for incremental prediction when the use_past is True. Default None.
 
         Outputs:
-            Tuple, a tuple contains(`output`, `encoder_layer_present`, `decoder_layer_present`)
+            Tuple, a tuple contains(`output`, `encoder_layer_present`, `decoder_layer_present`, `accum_loss`)
 
             - **output** (Tensor) - If there is only encoder, the output logit of the encoder layer. The shape is
               [batch, src_seq_length, hidden_size] or [batch * src_seq_length, hidden_size], if there are encoder and
@@ -2351,6 +2351,8 @@ class Transformer(Cell):
               (batch_size, num_heads, size_per_head, src_seq_length),
               (batch_size, num_heads, src_seq_length, size_per_head)). If the decoder is not set, the
               returned value will be None.
+            - **accum_loss** (Tensor) - A Tensor indicates an auxiliary loss to minimize the mean square of the data
+              part routed to each expert, and only returned if the number of experts is greater than 1.
 
         Supported Platforms:
             ``Ascend`` ``GPU``