Modifying #13

Author: koki0702

dezero/core.py

@@ -195,7 +195,7 @@ def __call__(self, *inputs):
             for output in outputs:
                 output.set_creator(self)
             self.inputs = inputs
-            self.outputs = [weakref.ref(y) for y in outputs]
+            self.outputs = [weakref.ref(output) for output in outputs]
 
         return outputs if len(outputs) > 1 else outputs[0]