UnpicklingError: Forbidden class: qlib.contrib.data.handler.Alpha158

[playgithub]

Env

pyqlib 0.9.8.dev26

Description

The error

UnpicklingError: Forbidden class: qlib.contrib.data.handler.Alpha158. Only whitelisted classes are allowed for security reasons. This is to prevent arbitrary code execution through pickle deserialization.

only happens in rolling train, i.e. Rolling._train_rolling_tasks,
not happen in unrolling train.

When downgrapde pyqlib to 0.9.7, the error disappears.