打印变量db的类（class）：
[root@fuel ~]# python
Python 2.6.6 (r266:84292, Jan 22 2014, 09:42:36)
[GCC 4.4.7 20120313 (Red Hat 4.4.7-4)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from nailgun.db import db
2016-01-28 15:33:57.512 DEBUG [7fa46d13f700] (settings) Looking for settings.yaml package config using old style __file__
2016-01-28 15:33:57.512 DEBUG [7fa46d13f700] (settings) Trying to read config file /usr/lib/python2.6/site-packages/nailgun/settings.yaml
2016-01-28 15:33:57.733 DEBUG [7fa46d13f700] (settings) Trying to read config file /etc/nailgun/settings.yaml
2016-01-28 15:33:57.752 DEBUG [7fa46d13f700] (settings) Trying to read config file /etc/fuel/version.yaml
>>> print db.__class__
<class 'sqlalchemy.orm.scoping.scoped_session'>
>>> print db.__class__.__name__
scoped_session
>>> exit()
# vi a.py
----------------------------------------------------------------
import re
from sqlalchemy.orm.scoping import scoped_session
d = scoped_session.__dict__
for var in d:
p = re.compile("__.*__")
m = p.search(var)
if m == None:
print "object.%s=%s" % (var, d[var])
----------------------------------------------------------------
# python a.py
object.add_all=<function do at 0x22a8050>
object.no_autoflush=<property object at 0x22a7310>
object.expunge_all=<function do at 0x22a8578>
object.scalar=<function do at 0x22a8938>
object.query=<function do at 0x22a87d0>
object.close_all=<classmethod object at 0x22a9398>
object.add=<function do at 0x22a5f50>
object.rollback=<function do at 0x22a88c0>
object.configure=<function configure at 0x22a5cf8>
object.query_property=<function query_property at 0x22a5d70>
object.is_active=<property object at 0x22a7260>
object.is_modified=<function do at 0x22a86e0>
object.info=<property object at 0x22a7368>
object.execute=<function do at 0x22a8398>
object.expunge=<function do at 0x22a8500>
object.refresh=<function do at 0x22a8848>
object.autoflush=<property object at 0x22a72b8>
object.merge=<function do at 0x22a8758>
object.dirty=<property object at 0x22a7100>
object.begin_nested=<function do at 0x22a8140>
object.delete=<function do at 0x22a8320>
object.remove=<function remove at 0x22a5c80>
object.flush=<function do at 0x22a85f0>
object.close=<function do at 0x22a81b8>
object.new=<property object at 0x22a71b0>
object.begin=<function do at 0x22a80c8>
object.identity_key=<classmethod object at 0x22a9478>
object.deleted=<property object at 0x22a7158>
object.identity_map=<property object at 0x22a7208>
object.expire=<function do at 0x22a8410>
object.object_session=<classmethod object at 0x22a9408>
object.bind=<property object at 0x22a70a8>
object.expire_all=<function do at 0x22a8488>
object.connection=<function do at 0x22a82a8>
object.commit=<function do at 0x22a8230>
object.get_bind=<function do at 0x22a8668>