Restore compatibility with zope.sqlalchemy 1.2

.gitignore

@@ -107,3 +107,6 @@ venv.bak/
 # mypy
 .mypy_cache/
 
+# data
+data.db
+dmarc-receive.conf

dmarcreceiver/model.py

@@ -1,13 +1,13 @@
-from zope.sqlalchemy import ZopeTransactionExtension
+import zope.sqlalchemy as zsqla
 from sqlalchemy import Column, Integer, String, Unicode, Enum, CheckConstraint, ForeignKey, DateTime, create_engine
 from sqlalchemy.orm import scoped_session, sessionmaker, relationship
 import sqlalchemy.types as satypes
 import sqlalchemy.dialects.postgresql as dpg
 from sqlalchemy.ext.declarative import declarative_base
 
-maker = sessionmaker(autoflush=True, autocommit=False,
-                     extension=ZopeTransactionExtension())
+maker = sessionmaker(autoflush=True, autocommit=False)
 DBSession = scoped_session(maker)
+zsqla.register(DBSession)
 
 DeclarativeBase = declarative_base()
 metadata = DeclarativeBase.metadata