modify pir in distribute api test (#2946)

Author: xiaoguoguo626807

distributed/CE_API/case/dist_fleet_static.py

@@ -62,6 +62,6 @@ def mlp(input_x, input_y, hid_dim=128, label_dim=2):
 step = 5
 train_info = []
 for i in range(step):
-    cost_val = exe.run(program=paddle.static.default_main_program(), feed=gen_data(), fetch_list=[cost.name])
+    cost_val = exe.run(program=paddle.static.default_main_program(), feed=gen_data(), fetch_list=[cost])
     train_info.append(cost_val[0])
 print(train_info)

distributed/CE_API/case/dist_train_launch.py

@@ -62,6 +62,6 @@ def mlp(input_x, input_y, hid_dim=128, label_dim=2):
 step = 5
 train_info = []
 for i in range(step):
-    cost_val = exe.run(program=paddle.static.default_main_program(), feed=gen_data(), fetch_list=[cost.name])
+    cost_val = exe.run(program=paddle.static.default_main_program(), feed=gen_data(), fetch_list=[cost])
     train_info.append(cost_val[0])
 print(train_info)