fix flatten code

resnet.py

@@ -1,3 +1,4 @@
+import torch
 import torch.nn as nn
 
 
@@ -174,7 +175,6 @@ class MaiRes(nn.Module):
         )
 
         self.avgpool = nn.AvgPool2d(kernel_size=RESNET_KERNEL_SIZE)
-        self.flatten = nn.Flatten()
         self.fc = nn.Linear(in_features=1000, out_features=1)
 
     def forward(self, x):
@@ -187,7 +187,7 @@ class MaiRes(nn.Module):
         x = self.layer_blue(x)
 
         x = self.avgpool(x)
-        x = self.flatten(x)
+        x = torch.flatten(x)
         x = self.fc(x)
 
         return x