gistfile1.py

def alias(column_name):
     """returns a descriptor that is usable everywhere the original column name
     was: (not really a doctest, sorry)

     >>> class Foo(SQLBase):
     ...     original = Column(Integer)
     ...     new = alias('original')

     >>> foo = Foo()
     >>> foo.new = 5
     >>> foo.original
     5
     >>> session.add(foo)
     >>> session.query(Foo).filter_by(new=5).count()
     1
     """

     # The declarative extension and sqlalchemy.orm.synonym() don't play
     # together without friction by themselves, so we give them a little nudge.
     def _get(self):
          return getattr(self, column_name)
     def _set(self, value):
          setattr(self, column_name, value)

     prop = property(_get, _set)
     return sqlalchemy.orm.synonym(column_name, descriptor=prop)