sqlalchemy.exc.InvalidRequestError: Table 'admin_users' is already defined for this MetaData instance.

gistfile1.txt

$ pserve development.ini --reload
Starting subprocess with file monitor
/Users/kwatch/myproj1/local/lib/python2.7/site-packages/SQLAlchemy-0.7.5-py2.7-macosx-10.4-x86_64.egg/sqlalchemy/ext/declarative.py:1336: SAWarning: The classname 'AdminUser' is already in the registry of this declarative base, mapped to <class 'smapo.common.models.base.AdminUser'>
  _as_declarative(cls, classname, cls.__dict__)
Traceback (most recent call last):
  File "/Users/kwatch/myproj1/local/bin/python2.7/pserve", line 9, in <module>
    load_entry_point('pyramid==1.3b2', 'console_scripts', 'pserve')()
  File "/Users/kwatch/myproj1/local/lib/python2.7/site-packages/pyramid-1.3b2-py2.7.egg/pyramid/scripts/pserve.py", line 47, in main
    return command.run()
  File "/Users/kwatch/myproj1/local/lib/python2.7/site-packages/pyramid-1.3b2-py2.7.egg/pyramid/scripts/pserve.py", line 290, in run
    relative_to=base, global_conf=vars)
  File "/Users/kwatch/myproj1/local/lib/python2.7/site-packages/pyramid-1.3b2-py2.7.egg/pyramid/scripts/pserve.py", line 318, in loadapp
    return loadapp(app_spec, name=name, relative_to=relative_to, **kw)
  File "/Users/kwatch/myproj1/local/lib/python2.7/site-packages/PasteDeploy-1.5.0-py2.7.egg/paste/deploy/loadwsgi.py", line 247, in loadapp
    return loadobj(APP, uri, name=name, **kw)
  File "/Users/kwatch/myproj1/local/lib/python2.7/site-packages/PasteDeploy-1.5.0-py2.7.egg/paste/deploy/loadwsgi.py", line 272, in loadobj
    return context.create()
  File "/Users/kwatch/myproj1/local/lib/python2.7/site-packages/PasteDeploy-1.5.0-py2.7.egg/paste/deploy/loadwsgi.py", line 710, in create
    return self.object_type.invoke(self)
  File "/Users/kwatch/myproj1/local/lib/python2.7/site-packages/PasteDeploy-1.5.0-py2.7.egg/paste/deploy/loadwsgi.py", line 146, in invoke
    return fix_call(context.object, context.global_conf, **context.local_conf)
  File "/Users/kwatch/myproj1/local/lib/python2.7/site-packages/PasteDeploy-1.5.0-py2.7.egg/paste/deploy/util.py", line 56, in fix_call
    val = callable(*args, **kw)
  File "/Users/kwatch/myproj1/smapo/__init__.py", line 65, in main
    config.scan('smapo')
  File "/Users/kwatch/myproj1/local/lib/python2.7/site-packages/pyramid-1.3b2-py2.7.egg/pyramid/config/__init__.py", line 912, in scan
    ignore=ignore)
  File "/Users/kwatch/myproj1/local/lib/python2.7/site-packages/venusian-1.0a3-py2.7.egg/venusian/__init__.py", line 179, in scan
    for importer, modname, ispkg in results:
  File "/Users/kwatch/myproj1/local/lib/python2.7/site-packages/venusian-1.0a3-py2.7.egg/venusian/__init__.py", line 337, in walk_packages
    __import__(name)
  File "/Users/kwatch/myproj1/smapo/models/__init__.py", line 1, in <module>
    #
  File "/Users/kwatch/myproj1/smapo/models/base.py", line 33, in <module>
  File "/Users/kwatch/myproj1/local/lib/python2.7/site-packages/SQLAlchemy-0.7.5-py2.7-macosx-10.4-x86_64.egg/sqlalchemy/ext/declarative.py", line 1336, in __init__
    _as_declarative(cls, classname, cls.__dict__)
  File "/Users/kwatch/myproj1/local/lib/python2.7/site-packages/SQLAlchemy-0.7.5-py2.7-macosx-10.4-x86_64.egg/sqlalchemy/ext/declarative.py", line 1235, in _as_declarative
    **table_kw)
  File "/Users/kwatch/myproj1/local/lib/python2.7/site-packages/SQLAlchemy-0.7.5-py2.7-macosx-10.4-x86_64.egg/sqlalchemy/schema.py", line 290, in __new__
    "existing Table object." % key)
sqlalchemy.exc.InvalidRequestError: Table 'admin_user' is already defined for this MetaData instance.  Specify 'extend_existing=True' to redefine options and columns on an existing Table object.