## This class causes the issue
class Category(Base):
    __tablename__ = "forum_category"
    id = Column('id',Integer,primary_key=True)
    name = Column('name', String(64))
    description = Column('description',Text)

    def __repr__(self):
        return self.name

## Handler which invokes
##class CategoriesPage(BaseHandler):
def get(self):
    categories = self.data.query(Category).order_by(Category).all()
    self.render("forums.html",categories=categories)

## This class doesn't

class Account(Base):
    __tablename__ = "account"
    id = Column('id',Integer,primary_key=True)
    username = Column('username', String(20))
    email = Column('email', String(32))
    password = Column('sha_pass_hash', String(32))
    joindate = Column('joindate', TIMESTAMP())
    gmlevel = Column('gmlevel',Integer(3))

    def __repr__(self):
        return self.username