Fix list_tail
Fix list_tail

cderici/pycket,pycket/pycket,samth/pycket,magnusmorton/pycket,krono/pycket,pycket/pycket,krono/pycket,pycket/pycket,krono/pycket,magnusmorton/pycket,vishesh/pycket,vishesh/pycket,cderici/pycket,samth/pycket,cderici/pycket,samth/pycket,vishesh/pycket,magnusmorton/pycket