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Greetings!
I'm compiling one of the Fuel components, which named nailgun.
Before build it, I need to create the database, but it shows the 
following error:
~~~
2014-01-07 21:38:23.653 INFO [7fdbe5f30700] (manage) Syncing database...
Traceback (most recent call last):
   File "./manage.py", line 114, in <module>
     from nailgun.db import syncdb
   File "/root/Fuel/fuel-web/nailgun/nailgun/db/__init__.py", line 17, 
in <module>
     from nailgun.db.sqlalchemy import db
   File "/root/Fuel/fuel-web/nailgun/nailgun/db/sqlalchemy/__init__.py", 
line 31, in <module>
     engine = create_engine(db_str, client_encoding='utf8')
   File 
"/usr/lib/python2.6/site-packages/sqlalchemy/engine/__init__.py", line 
223, in create_engine
     return strategy.create(*args, **kwargs)
   File 
"/usr/lib/python2.6/site-packages/sqlalchemy/engine/strategies.py", line 
48, in create
     dialect_cls = u.get_dialect()
   File "/usr/lib/python2.6/site-packages/sqlalchemy/engine/url.py", 
line 91, in get_dialect
     module = getattr(__import__('sqlalchemy.databases.%s' % 
self.drivername).databases, self.drivername)
ImportError: No module named postgresql
~~~
I installed psycopg2, also failed. Which package provides the PostgreSQL 
driver for python? And the driver name is "postgresql"
Cheers,
Kevein