So there’s an add_module method that lets me add modules, but how do I remove/replace them?  For the time being, del works, but feels really dirty.
class net(nn.Module):
    def __init__(self):
        self.relu = nn.ReLU()
    def change(self):
        try:
            del self.relu #DIRTY
        except:
            pass
        def fun(x):
            return x
        self.relu = fun #crashes without the del statement...
    def forward(self,x):
        return self.relu(x)