Maybe this recipe is useful:

  
    
    
    Can I get the middle layer's output if I use the Sequential module? 
  
  
    You could just iterate the application yourself: 
x = someinput
for l in vgg.features.modules():
  x = l(x)

and keep what you want. 
You can slice the modules by wrapping the in a list, so: 
modulelist = list(vgg.features.modules())
for l in modulelist[:5]:
  x = l(x)
keep = x
for l in modulelist[5:]:
  x = l(x)

Best regards 
Thomas
  


Best regards
Thomas