diff --git a/dygraph/models/hrnet.py b/dygraph/models/hrnet.py
index 069e6c741b584b2bc3904a64c7d4fb7887d8ea77..a47c63c6e488bcfa343e704a5a78b54e908bdf8f 100644
--- a/dygraph/models/hrnet.py
+++ b/dygraph/models/hrnet.py
@@ -20,12 +20,7 @@ from paddle.fluid.param_attr import ParamAttr
 from paddle.fluid.layer_helper import LayerHelper
 from paddle.fluid.dygraph.nn import Conv2D, Pool2D, Linear
 from paddle.fluid.initializer import Normal
-try:
-    from paddle.fluid.dygraph import SyncBatchNorm as BatchNorm
-    print('using sync batch norm')
-except:
-    from paddle.fluid.dygraph import BatchNorm
-    print('using batch norm')
+from paddle.fluid.dygraph import SyncBatchNorm as BatchNorm
 
 __all__ = [
     "HRNet_W18_Small_V1", "HRNet_W18_Small_V2", "HRNet_W18", "HRNet_W30",
diff --git a/dygraph/models/unet.py b/dygraph/models/unet.py
index 8474c2cf3d768fec8294fa8c674a84422b15966e..6f04643a29bd1dbfd18f1ed162852d4758910f26 100644
--- a/dygraph/models/unet.py
+++ b/dygraph/models/unet.py
@@ -14,15 +14,12 @@
 
 import paddle.fluid as fluid
 from paddle.fluid.dygraph import Conv2D, Pool2D
-try:
-    from paddle.fluid.dygraph import SyncBatchNorm as BatchNorm
-except:
-    from paddle.fluid.dygraph import BatchNorm
+from paddle.fluid.dygraph import SyncBatchNorm as BatchNorm
 
 
 class UNet(fluid.dygraph.Layer):
     def __init__(self, num_classes, ignore_index=255):
-        super().__init__()
+        super(UNet, self).__init__()
         self.encode = UnetEncoder()
         self.decode = UnetDecode()
         self.get_logit = GetLogit(64, num_classes)
@@ -65,7 +62,7 @@ class UNet(fluid.dygraph.Layer):
 
 class UnetEncoder(fluid.dygraph.Layer):
     def __init__(self):
-        super().__init__()
+        super(UnetEncoder, self).__init__()
         self.double_conv = DoubleConv(3, 64)
         self.down1 = Down(64, 128)
         self.down2 = Down(128, 256)
@@ -88,7 +85,7 @@ class UnetEncoder(fluid.dygraph.Layer):
 
 class UnetDecode(fluid.dygraph.Layer):
     def __init__(self):
-        super().__init__()
+        super(UnetDecode, self).__init__()
         self.up1 = Up(512, 256)
         self.up2 = Up(256, 128)
         self.up3 = Up(128, 64)
@@ -104,7 +101,7 @@ class UnetDecode(fluid.dygraph.Layer):
 
 class DoubleConv(fluid.dygraph.Layer):
     def __init__(self, num_channels, num_filters):
-        super().__init__()
+        super(DoubleConv, self).__init__()
         self.conv0 = Conv2D(
             num_channels=num_channels,
             num_filters=num_filters,
@@ -132,7 +129,7 @@ class DoubleConv(fluid.dygraph.Layer):
 
 class Down(fluid.dygraph.Layer):
     def __init__(self, num_channels, num_filters):
-        super().__init__()
+        super(Down, self).__init__()
         self.max_pool = Pool2D(
             pool_size=2, pool_type='max', pool_stride=2, pool_padding=0)
         self.double_conv = DoubleConv(num_channels, num_filters)
@@ -145,7 +142,7 @@ class Down(fluid.dygraph.Layer):
 
 class Up(fluid.dygraph.Layer):
     def __init__(self, num_channels, num_filters):
-        super().__init__()
+        super(Up, self).__init__()
         self.double_conv = DoubleConv(2 * num_channels, num_filters)
 
     def forward(self, x, short_cut):
@@ -158,7 +155,7 @@ class Up(fluid.dygraph.Layer):
 
 class GetLogit(fluid.dygraph.Layer):
     def __init__(self, num_channels, num_classes):
-        super().__init__()
+        super(GetLogit, self).__init__()
         self.conv = Conv2D(
             num_channels=num_channels,
             num_filters=num_classes,