python save/load tutorial, small fix
python save/load tutorial, small fix


Former-commit-id: e22096ccbd233fbfc7491ab7b1170f8c4e9ce94e
shuheik/dynet,shuheik/dynet,xunzhang/dynet,clab/dynet,clab/dynet,clab/dynet,clab/cnn,clab/cnn,clab/cnn,xunzhang/dynet,shuheik/dynet,chunyang-wen/dynet,chunyang-wen/dynet,chunyang-wen/dynet,danielhers/dynet,xunzhang/dynet,danielhers/dynet,danielhers/dynet,clab/dynet,shuheik/dynet,xunzhang/dynet,clab/dynet,shuheik/dynet,danielhers/dynet,shuheik/dynet,danielhers/dynet,clab/dynet,chunyang-wen/dynet,danielhers/dynet,shuheik/dynet,clab/dynet,danielhers/dynet