diff --git a/qlib/model/riskmodel/shrink.py b/qlib/model/riskmodel/shrink.py
index b2594f707d..c3c0e48ef8 100644
--- a/qlib/model/riskmodel/shrink.py
+++ b/qlib/model/riskmodel/shrink.py
@@ -247,9 +247,7 @@ def _get_shrink_param_lw_single_factor(self, X: np.ndarray, S: np.ndarray, F: np
         v1 = y.T.dot(z) / t - cov_mkt[:, None] * S
         roff1 = np.sum(v1 * cov_mkt[:, None].T) / var_mkt - np.sum(np.diag(v1) * cov_mkt) / var_mkt
         v3 = z.T.dot(z) / t - var_mkt * S
-        roff3 = (
-            np.sum(v3 * np.outer(cov_mkt, cov_mkt)) / var_mkt**2 - np.sum(np.diag(v3) * cov_mkt**2) / var_mkt**2
-        )
+        roff3 = np.sum(v3 * np.outer(cov_mkt, cov_mkt)) / var_mkt**2 - np.sum(np.diag(v3) * cov_mkt**2) / var_mkt**2
         roff = 2 * roff1 - roff3
         rho = rdiag + roff
 
diff --git a/qlib/utils/index_data.py b/qlib/utils/index_data.py
index 715040538a..6c4525ce36 100644
--- a/qlib/utils/index_data.py
+++ b/qlib/utils/index_data.py
@@ -141,8 +141,8 @@ def _convert_type(self, item):
             elif isinstance(item, np.datetime64):
                 # This happens often when creating index based on np.datetime64 and query with another precision
                 return item.astype(self.idx_list.dtype)
-            # NOTE: It is hard to consider every case at first. 
-            # We just try to cover part of cases to make it more user-friendly 
+            # NOTE: It is hard to consider every case at first.
+            # We just try to cover part of cases to make it more user-friendly
         return item
 
     def index(self, item) -> int: