ob-python noweb and :var reference error

[stardiviner <numbchild@gmail.com>]

I installed python packages through `pip`:

#+begin_src shell
pip install deluge-client
#+end_src

If you want to test those src blocks, you also need to make sure Deluge 
installed and daemon started.

And use `deluge-client` like this:

#+NAME: deluge-daemon-username
#+begin_src shell
cat ~/.config/deluge/auth | cut -d ":" -f 1
#+end_src

#+RESULTS: deluge-daemon-username
: localclient

#+NAME: deluge-daemon-password
#+begin_src shell
cat ~/.config/deluge/auth | cut -d ":" -f 2
#+end_src

#+RESULTS: deluge-daemon-password
: 9b83ceded9ac08cc5c7403b093115874a6086958

#+begin_src python :noweb yes :results list
from deluge_client import DelugeRPCClient

client = DelugeRPCClient('127.0.0.1', 58846, username, password)
client.connect()
client.connected # True
client.call('core.get_torrents_status', {}, ['name'])
#=> {'79816060ea56d56f2a2148cd45705511079f9bca': {'name': 
'TPB.AFK.2013.720p.h264-SimonKlose'}}
#+end_src


But got error:

```

Traceback (most recent call last):
   File "<stdin>", line 15, in <module>
   File "<stdin>", line 10, in main
   File 
"/home/stardiviner/.virtualenvs/python3.6/lib/python3.6/site-packages/deluge_client/client.py", 
line 62, in connect
     result = self.call('daemon.login', self.username, self.password)
   File 
"/home/stardiviner/.virtualenvs/python3.6/lib/python3.6/site-packages/deluge_client/client.py", 
line 110, in call
     raise exception(exception_msg)
deluge_client.client.b'BadLoginError': b'Username does not exist'

b'  File "/usr/lib/python2.7/site-packages/deluge/core/rpcserver.py", 
line 262, in dispatch\n    ret = 
component.get("AuthManager").authorize(*args, **kwargs)\n  File 
"/usr/lib/python2.7/site-packages/deluge/core/authmanager.py", line 89, 
in authorize\n    raise BadLoginError("Username does not exist")\n'
```