diff --git a/mindarmour/adv_robustness/attacks/attack.py b/mindarmour/adv_robustness/attacks/attack.py
index e138407..f7c6a37 100644
--- a/mindarmour/adv_robustness/attacks/attack.py
+++ b/mindarmour/adv_robustness/attacks/attack.py
@@ -183,13 +183,12 @@ class Attack:
         best_position = check_numpy_param('best_position', best_position)
         x_ori, best_position = check_equal_shape('x_ori', x_ori, 'best_position', best_position)
         _, original_num = self._detection_scores((best_position,) + auxiliary_inputs, gt_boxes, gt_labels, model)
-        # pylint: disable=invalid-name
-        REDUCTION_ITERS = 6  # recover 10% difference each time and recover 60% totally.
-        for _ in range(REDUCTION_ITERS):
-            BLOCK_NUM = 30  # divide the image into 30 segments
-            block_width = best_position.shape[0] // BLOCK_NUM
+        reduction_iters = 6  # recover 10% difference each time and recover 60% totally.
+        for _ in range(reduction_iters):
+            block_num = 30  # divide the image into 30 segments
+            block_width = best_position.shape[0] // block_num
             if block_width > 0:
-                for i in range(BLOCK_NUM):
+                for i in range(block_num):
                     diff = x_ori[i*block_width: (i+1)*block_width, :, :]\
                            - best_position[i*block_width:(i+1)*block_width, :, :]
                     if np.max(np.abs(diff)) >= 0.1*(self._bounds[1] - self._bounds[0]):
diff --git a/mindarmour/fuzz_testing/image_transform.py b/mindarmour/fuzz_testing/image_transform.py
index 52a1136..04c4309 100644
--- a/mindarmour/fuzz_testing/image_transform.py
+++ b/mindarmour/fuzz_testing/image_transform.py
@@ -107,8 +107,8 @@ def is_normalized(img):
     """
     if is_numpy(img):
         minimal = np.min(img)
-        maximun = np.max(img)
-        if minimal >= 0 and maximun <= 1:
+        maximum = np.max(img)
+        if minimal >= 0 and maximum <= 1:
             return True
         return False
     raise TypeError('img should be Numpy array. Got {}'.format(type(img)))
@@ -359,9 +359,9 @@ class Translate(ImageTransform):
     Translate an image.
 
     Args:
-        x_bias (Union[int, float]): X-direction translation, x = x + x_bias*image_length.
+        x_bias (Union[int, float]): X-direction translation: x + x_bias*image_length.
             Default: 0.
-        y_bias (Union[int, float]): Y-direction translation,  y = y + y_bias*image_wide.
+        y_bias (Union[int, float]): Y-direction translation: y + y_bias*image_wide.
             Default: 0.
     """
 
diff --git a/mindarmour/privacy/diff_privacy/monitor/monitor.py b/mindarmour/privacy/diff_privacy/monitor/monitor.py
index 62449c1..ef6ef10 100644
--- a/mindarmour/privacy/diff_privacy/monitor/monitor.py
+++ b/mindarmour/privacy/diff_privacy/monitor/monitor.py
@@ -347,9 +347,8 @@ class RDPMonitor(Callback):
         Returns:
             float, delta budget.
         """
-        orders = np.atleast_1d(self._orders)
         rdps = np.atleast_1d(rdp)
-        deltas = np.exp((rdps - self._target_eps)*(orders - 1))
+        deltas = np.exp((rdps - self._target_eps)*(np.atleast_1d(self._orders) - 1))
         min_delta = np.min(deltas)
         return np.min([min_delta, 1.])
 
@@ -363,9 +362,8 @@ class RDPMonitor(Callback):
         Returns:
             float, eps budget.
         """
-        orders = np.atleast_1d(self._orders)
         rdps = np.atleast_1d(rdp)
-        eps = rdps - np.log(self._target_delta) / (orders - 1)
+        eps = rdps - np.log(self._target_delta) / (np.atleast_1d(self._orders) - 1)
         return np.min(eps)
 
 
diff --git a/mindarmour/privacy/sup_privacy/mask_monitor/masker.py b/mindarmour/privacy/sup_privacy/mask_monitor/masker.py
index 4b9e629..09926d2 100644
--- a/mindarmour/privacy/sup_privacy/mask_monitor/masker.py
+++ b/mindarmour/privacy/sup_privacy/mask_monitor/masker.py
@@ -26,7 +26,7 @@ TAG = 'suppress masker'
 class SuppressMasker(Callback):
     """
     Args:
-        model (SuppressModel):  SuppressModel instance.
+        model (SuppressModel): SuppressModel instance.
         suppress_ctrl (SuppressCtrl): SuppressCtrl instance.
 
     Examples:
diff --git a/mindarmour/privacy/sup_privacy/train/model.py b/mindarmour/privacy/sup_privacy/train/model.py
index 0e08de9..86fc041 100644
--- a/mindarmour/privacy/sup_privacy/train/model.py
+++ b/mindarmour/privacy/sup_privacy/train/model.py
@@ -225,7 +225,6 @@ class _TupleMul(nn.Cell):
     def construct(self, input1, input2):
         """Add two tuple of data."""
         out = self.hyper_map(self.mul, input1, input2)
-        #print(out)
         return out
 
 # come from nn.cell_wrapper.TrainOneStepCell
diff --git a/mindarmour/reliability/concept_drift/concept_drift_check_images.py b/mindarmour/reliability/concept_drift/concept_drift_check_images.py
index ec0046b..84aa335 100644
--- a/mindarmour/reliability/concept_drift/concept_drift_check_images.py
+++ b/mindarmour/reliability/concept_drift/concept_drift_check_images.py
@@ -11,20 +11,22 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-# ============================================================================
-
+"""
+Out-of-Distribution detection for images.
+"""
 
 import heapq
+from abc import abstractmethod
 import numpy as np
-from mindspore import Tensor
 from sklearn.cluster import KMeans
-from mindarmour.utils._check_param import check_param_type, check_param_in_range
-from mindspore.train.summary.summary_record import _get_summary_tensor_data
 
+from mindspore.train.summary.summary_record import _get_summary_tensor_data
+from mindspore import Tensor
+from mindarmour.utils._check_param import check_param_type, check_param_in_range
+from mindarmour.utils.logger import LogUtil
 
-"""
-Out-of-Distribution detection for images.
-"""
+LOGGER = LogUtil.get_instance()
+TAG = 'concept drift detection'
 
 
 class OodDetector:
@@ -56,6 +58,7 @@ class OodDetector:
         layer_out = _get_summary_tensor_data()
         return layer_out[layer].asnumpy()
 
+    @abstractmethod
     def get_optimal_threshold(self, label, ds_eval):
         """
         Get the optimal threshold.
@@ -67,8 +70,12 @@ class OodDetector:
         Returns:
             - float, the optimal threshold.
         """
-        pass
+        msg = 'The function generate() is an abstract function in class ' \
+              '`OodDetector` and should be implemented in child class.'
+        LOGGER.error(TAG, msg)
+        raise NotImplementedError(msg)
 
+    @abstractmethod
     def ood_predict(self, threshold, ds_test):
         """
         The out-of-distribution detection.
@@ -81,7 +88,10 @@ class OodDetector:
         Returns:
            - numpy.ndarray, the detection result. 0 means the data is not ood, 1 means the data is ood.
         """
-        pass
+        msg = 'The function generate() is an abstract function in class ' \
+              '`OodDetector` and should be implemented in child class.'
+        LOGGER.error(TAG, msg)
+        raise NotImplementedError(msg)
 
 
 class OodDetectorFeatureCluster(OodDetector):
@@ -103,6 +113,7 @@ class OodDetectorFeatureCluster(OodDetector):
     """
 
     def __init__(self, model, ds_train, n_cluster, layer):
+        super().__init__(model, ds_train)
         self.model = model
         self.ds_train = check_param_type('ds_train', ds_train, np.ndarray)
         self.n_cluster = check_param_type('n_cluster', n_cluster, int)
@@ -173,7 +184,7 @@ class OodDetectorFeatureCluster(OodDetector):
             threshold.append(threshold_change)
         acc = np.array(acc)
         threshold = np.array(threshold)
-        optimal_threshold = threshold[np.where(acc==np.max(acc))[0]][0]
+        optimal_threshold = threshold[np.where(acc == np.max(acc))[0]][0]
         return optimal_threshold
 
     def ood_predict(self, threshold, ds_test):
diff --git a/mindarmour/reliability/concept_drift/concept_drift_check_time_series.py b/mindarmour/reliability/concept_drift/concept_drift_check_time_series.py
index 61e553f..f3be9f4 100644
--- a/mindarmour/reliability/concept_drift/concept_drift_check_time_series.py
+++ b/mindarmour/reliability/concept_drift/concept_drift_check_time_series.py
@@ -9,7 +9,6 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-# ============================================================================
 
 """
 Concpt drift module
@@ -72,8 +71,7 @@ class ConceptDriftCheckTimeSeries:
             >>> w, x = ConceptDriftCheckTimeSeries._reservoir_model_feature(window_data)
         """
         # Initialize weights
-        res_size = self._res_size
-        x_state = _w_generate(res_size, len(window_data), window_data)
+        x_state = _w_generate(self._res_size, len(window_data), window_data)
         x_state_t = x_state.T
         # Data reshape
         data_channel = None
@@ -85,7 +83,7 @@ class ConceptDriftCheckTimeSeries:
         reg = 1e-8
         # Calculate w_out
         w_out = np.dot(np.dot(y_t, x_state_t),
-                       np.linalg.inv(np.dot(x_state, x_state_t) + reg*np.eye(res_size)))
+                       np.linalg.inv(np.dot(x_state, x_state_t) + reg*np.eye(self._res_size)))
         return w_out, x_state
 
     def _concept_distance(self, data_x, data_y):
@@ -391,11 +389,11 @@ def _cal_threshold(distance, threshold_index):
     Returns:
         - float, [0, 1].
     """
-    distance = distance[distance > 0]
+    pos_distance = distance[distance > 0]
     # Threshold calculation
-    if distance.size > 0:
-        q_1 = np.percentile(distance, 25)
-        q_3 = np.percentile(distance, 75)
+    if pos_distance.size > 0:
+        q_1 = np.percentile(pos_distance, 25)
+        q_3 = np.percentile(pos_distance, 75)
         q_diff = q_3 - q_1
         threshold = np.clip(0.1 + threshold_index*q_diff, 0, 1)
     else:
diff --git a/mindarmour/reliability/model_fault_injection/__init__.py b/mindarmour/reliability/model_fault_injection/__init__.py
index f2c861a..655bb9a 100644
--- a/mindarmour/reliability/model_fault_injection/__init__.py
+++ b/mindarmour/reliability/model_fault_injection/__init__.py
@@ -8,7 +8,6 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-# ============================================================================
 """
 This module provides model fault injection to evaluate the reliability of given model.
 """
diff --git a/mindarmour/reliability/model_fault_injection/fault_injection.py b/mindarmour/reliability/model_fault_injection/fault_injection.py
index 9f7d4ec..01a8c59 100644
--- a/mindarmour/reliability/model_fault_injection/fault_injection.py
+++ b/mindarmour/reliability/model_fault_injection/fault_injection.py
@@ -8,7 +8,6 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-# ============================================================================
 
 """
 Fault injection module
diff --git a/mindarmour/reliability/model_fault_injection/fault_type.py b/mindarmour/reliability/model_fault_injection/fault_type.py
index 6e40c22..5adc3ef 100644
--- a/mindarmour/reliability/model_fault_injection/fault_type.py
+++ b/mindarmour/reliability/model_fault_injection/fault_type.py
@@ -8,7 +8,6 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-# ============================================================================
 
 """
 Fault type module