[Sqlalchemy-tickets] Issue #4263: MapperEvents before_update, after_update do not work (zzzeek/sqlalchemy)

[Karol N. <iss...@bi...>]

New issue 4263: MapperEvents before_update, after_update do not work
https://bitbucket.org/zzzeek/sqlalchemy/issues/4263/mapperevents-before_update-after_update-do

Karol Narowski:

Function is not called when set in listener. **before_insert** and **after_insert** is working well but **before_update** and **after_update** are not called.
Ex.

```
#!python
class User(Base):
    __tablename__ = 'users'

    uid = Column(String(36), primary_key=True, unique=True, default=generate_uuid)
    name = Column(String(15), nullable=False)
    description = Column(String(25), nullable=False)
    phone = Column(String(20), nullable=False)
    hash = Column(String(128), nullable=True, unique=True)
    created_on = Column(DateTime(), default=datetime.utcnow)
    updated_on = Column(DateTime(), default=datetime.utcnow, onupdate=datetime.utcnow)
@listens_for(User, 'before_insert')
def before_insert_function(mapper, connection, target):
    print(target.phone)
    target.hash = "OtherInsert"


@listens_for(User, 'before_update')
def before_update_function(mapper, connection, target):
    print(target.uid)
    print(target.phone)
    target.hash = "OtherUpdate"

```