bug fixes

Author: christinafan

modin/core/storage_formats/pandas/query_compiler.py

@@ -44,6 +44,7 @@
 
 from modin.core.storage_formats.base.query_compiler import BaseQueryCompiler
 from modin.config import ExperimentalGroupbyImpl
+from modin.config import Engine
 from modin.error_message import ErrorMessage
 from modin.utils import (
     try_cast_to_pandas,

modin/pandas/window.py

@@ -183,7 +183,7 @@ def sum(self, *args, **kwargs):
     def mean(self, *args, **kwargs):
         return self._dataframe.__constructor__(
             query_compiler=self._query_compiler.rolling_mean(
-                self.axis, rolling_args=self.rolling_kwargs, *args, **kwargs
+                self.axis, self.rolling_kwargs, *args, **kwargs
             )
         )