Python 烧瓶嘶嘶炼金术不起作用：此会话处于'；承诺'；国家；在此事务中不能发出进一步的SQL

我正在编写一个脚本，将一些数据从CSV文件导入Postgres数据库。脚本如下：

app = Flask(__name__)

app.config['SQLALCHEMY_DATABASE_URI'] = <my-db-uri>
app.config['WHOOSH_INDEX_PATH'] = <my-whoosh-directory-path>

db = flask_sqlalchemy.SQLAlchemy(app)

class MyClass(db.Model):
    __tablename__ = 'my_table'
    __searchable__ = ['first_param']

    first_param = db.Column(db.Unicode)
    second_param = db.Column(db.Unicode)
    third_param = db.Column(db.Unicode)

def load_data(filepath, session):
    try:
        with open(filepath, 'r', encoding=encoding) as file:
            datareader = csv.reader(file, delimiter=';')
            headers = next(datareader)

            for row in datareader:
                entry = {row[i] for i, c in enumerate(headers)}
                session.add(MyClass(**entry))

            session.commit()

            return True
    except Exception as e:
        session.rollback()

        return False
    finally:
        session.remove()

if __name__ == '__main__':
    db.create_all()

    data_loaded = load_data(filepath = <my-file-path>, session = db.session)

有人知道问题出在哪里吗？我试图找到一个解决方案，但没有找到

This session is in 'committed' state; no further SQL can be emitted within this transaction.
Traceback (most recent call last):
  File "data_importer.py", line 169, in load_data
    session.commit()
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/scoping.py", line 157, in do
    return getattr(self.registry(), name)(*args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/session.py", line 906, in commit
    self.transaction.commit()
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/session.py", line 468, in commit
    self.session.dispatch.after_commit(self.session)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/event/attr.py", line 256, in __call__
    fn(*args, **kw)
  File "/usr/local/lib/python3.7/site-packages/flask_sqlalchemy/__init__.py", line 219, in after_commit
    models_committed.send(session.app, changes=list(d.values()))
  File "/usr/local/lib/python3.7/site-packages/blinker/base.py", line 267, in send
    for receiver in self.receivers_for(sender)]
  File "/usr/local/lib/python3.7/site-packages/blinker/base.py", line 267, in <listcomp>
    for receiver in self.receivers_for(sender)]
  File "/usr/local/lib/python3.7/site-packages/flask_whooshalchemy/__init__.py", line 153, in _post_flush
    attrs[k] = str(getattr(v, k))
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/attributes.py", line 237, in __get__
    return self.impl.get(instance_state(instance), dict_)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/attributes.py", line 579, in get
    value = state._load_expired(state, passive)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/state.py", line 592, in _load_expired
    self.manager.deferred_scalar_loader(self, toload)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/loading.py", line 698, in load_scalar_attributes
    only_load_props=attribute_names)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/loading.py", line 223, in load_on_ident
    return q.one()
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/query.py", line 2814, in one
    ret = self.one_or_none()
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/query.py", line 2784, in one_or_none
    ret = list(self)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/query.py", line 2855, in __iter__
    return self._execute_and_instances(context)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/query.py", line 2876, in _execute_and_instances
    close_with_result=True)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/query.py", line 2885, in _get_bind_args
    **kw
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/query.py", line 2867, in _connection_from_session
    conn = self.session.connection(**kw)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/session.py", line 998, in connection
    execution_options=execution_options)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/session.py", line 1003, in _connection_for_bind
    engine, execution_options)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/session.py", line 382, in _connection_for_bind
    self._assert_active()
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/session.py", line 258, in _assert_active
    "This session is in 'committed' state; no further "
sqlalchemy.exc.InvalidRequestError: This session is in 'committed' state; no further SQL can be emitted within this transaction.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "data_importer_2.py", line 459, in <module>
    ldap_data_loaded = load_data(filepath = args.data_dir, session = db.session, added_on=last_update)
  File "data_importer_2.py", line 180, in load_data
    session.rollback()
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/scoping.py", line 157, in do
    return getattr(self.registry(), name)(*args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/session.py", line 870, in rollback
    self.transaction.rollback()
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/session.py", line 477, in rollback
    self._assert_active(prepared_ok=True, rollback_ok=True)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/session.py", line 258, in _assert_active
    "This session is in 'committed' state; no further "
sqlalchemy.exc.InvalidRequestError: This session is in 'committed' state; no further SQL can be emitted within this transaction.