[Sqlalchemy-tickets] Issue #3798: _add_bind() not covered / doesn't import exception (zzzeek/sqlalchemy)

[Michael B. <iss...@bi...>]

New issue 3798: _add_bind() not covered / doesn't import exception
https://bitbucket.org/zzzeek/sqlalchemy/issues/3798/_add_bind-not-covered-doesnt-import

Michael Bayer:


```
#!python

from sqlalchemy.orm import Session

s = Session()

s.bind_mapper("boom", "Foo")


python test.py
Traceback (most recent call last):
  File "test.py", line 5, in <module>
    s.bind_mapper("boom", "Foo")
  File "/home/classic/dev/sqlalchemy/lib/sqlalchemy/orm/session.py", line 1150, in bind_mapper
    self._add_bind(mapper, bind)
  File "/home/classic/dev/sqlalchemy/lib/sqlalchemy/orm/session.py", line 1125, in _add_bind
    raise exc.ArgumentError(
AttributeError: 'module' object has no attribute 'ArgumentError'

```