title: pytorch nn.Sequential(*list) TypeError: list is not a Module subclass
body: <p>when I use pytorch to train a model, I tried to print the whole net structure</p>
  
  <p>so I packed all the layers in a list
  then I use <code>nn.Sequential(*list)</code></p>
  
  <p>but it doesn't work, and the TypeError: list is not a Module subclass</p>