Module object has no attribute [CANTERA]

问题:

I've been trying out the simpliest basics of Cantera. I'm using Cantera 2.2.1 installed on CAE Linux (Xubuntu 12.04) along with iPython.

I first import:

import cantera as ct

Then I try creating a gas:

gas = ct.Solution('gri30.xml')

That is just a tutorial copycat. Yet it seems not to work at all. What i get is

AttributeError: 'module' object has no attribute 'Solution'

I wish to know what can a reason behind this all be.