RE: builtins.NoneType' is not mapped

[Clive Swan]

Greetings,

I am getting the following error, any suggestions would be welcomed.

When running: 

deleteVersionStamp     self.session.delete(rec)   File “\Externals\win32\Lib\site-packages\sqlalchemy\orm\scoping.py”, line 162,

in do     return getattr(self.registry(), name)(*args, **kwargs)   File " \Externals\win32\Lib\site-packages\sqlalchemy\orm\session.py", line 2014,

in delete     util.raise_(   File " \Externals\win32\Lib\site-packages\sqlalchemy\util\compat.py", line 178, in raise_     raise exception sqlalchemy.orm.exc.UnmappedInstanceError: Class 'builtins.NoneType' is not mapped

Class 'builtins.NoneType' is not mapped

Is this a permissions error or something else??

Thanks,

Clive