In this neural networks tutorial
http://pytorch.org/tutorials/beginner/blitz/neural_networks_tutorial.html#sphx-glr- 53
beginner-blitz-neural-networks-tutorial-py
I got an error in here:
print(loss.grad_fn)  # MSELoss
print(loss.grad_fn.next_functions[0][0])  # Linear
print(loss.grad_fn.next_functions[0][0].next_functions[0][0])  # ReLU


---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-30-95cc2826ff61> in <module>()
----> 1 print(loss.grad_fn)  # MSELoss
      2 print(loss.grad_fn.next_functions[0][0])  # Linear
      3 print(loss.grad_fn.next_functions[0][0].next_functions[0][0])  # ReLU

/usr/local/lib/python2.7/dist-packages/torch/autograd/variable.pyc in __getattr__(self, name)
     61         if name in self._fallthrough_methods:
     62             return getattr(self.data, name)
---> 63         raise AttributeError(name)
     64 
     65     def __getitem__(self, key):

AttributeError: grad_fn