diff --git a/qlib/contrib/data/handler.py b/qlib/contrib/data/handler.py
index 40f211c1c..54e9de27f 100644
--- a/qlib/contrib/data/handler.py
+++ b/qlib/contrib/data/handler.py
@@ -2,11 +2,11 @@
 # Licensed under the MIT License.
 
 from ...data.dataset.handler import DataHandlerLP
-from ...data.dataset.processor import Processor, MinMaxNorm, ZscoreNorm
-from ...utils import get_cls_kwargs, get_module_by_module_path
+from ...data.dataset.processor import Processor
+from ...utils import get_cls_kwargs
 from ...data.dataset import processor as processor_module
 from ...log import TimeInspector
-from inspect import isclass
+from inspect import getfullargspec
 import copy
 
 
@@ -100,11 +100,11 @@ class Alpha158(DataHandlerLP):
             for p in proc_l:
                 if not isinstance(p, Processor):
                     klass, pkwargs = get_cls_kwargs(p, processor_module)
-                    processors = get_module_by_module_path(processor_module.__name__)
-                    if klass.__name__ in [c for c in dir(processor_module) if isclass(getattr(processor_module, c))]:
+                    args = getfullargspec(klass).args
+                    if "fit_start_time" in args and "fit_end_time" in args:
                         assert (
                             fit_start_time is not None and fit_end_time is not None
-                        ), "Make sure fit_start_time and fit_end_time are not None."
+                        ), "Make sure `fit_start_time` and `fit_end_time` are not None."
                         pkwargs.update(
                             {
                                 "fit_start_time": fit_start_time,