diff --git a/paddlers/models/ppcls/utils/model_zoo.py b/paddlers/models/ppcls/utils/model_zoo.py
index bad0752..d9436fe 100644
--- a/paddlers/models/ppcls/utils/model_zoo.py
+++ b/paddlers/models/ppcls/utils/model_zoo.py
@@ -151,26 +151,28 @@ def _decompress(fname):
 
     if fname.find('tar') >= 0:
         with tarfile.open(fname) as tf:
-            def is_within_directory(directory, target):
-                
+
+            def _is_within_directory(directory, target):
                 abs_directory = os.path.abspath(directory)
                 abs_target = os.path.abspath(target)
-            
+
                 prefix = os.path.commonprefix([abs_directory, abs_target])
-                
+
                 return prefix == abs_directory
-            
-            def safe_extract(tar, path=".", members=None, *, numeric_owner=False):
-            
+
+            def _safe_extract(tar,
+                              path=".",
+                              members=None,
+                              *,
+                              numeric_owner=False):
                 for member in tar.getmembers():
                     member_path = os.path.join(path, member.name)
-                    if not is_within_directory(path, member_path):
+                    if not _is_within_directory(path, member_path):
                         raise Exception("Attempted Path Traversal in Tar File")
-            
-                tar.extractall(path, members, numeric_owner=numeric_owner) 
-                
-            
-            safe_extract(tf, path=fpath_tmp)
+
+                tar.extractall(path, members, numeric_owner=numeric_owner)
+
+            _safe_extract(tf, path=fpath_tmp)
     elif fname.find('zip') >= 0:
         with zipfile.ZipFile(fname) as zf:
             zf.extractall(path=fpath_tmp)
diff --git a/paddlers/utils/download.py b/paddlers/utils/download.py
index 435ad17..56cf30e 100644
--- a/paddlers/utils/download.py
+++ b/paddlers/utils/download.py
@@ -151,26 +151,28 @@ def decompress(fname):
 
     if fname.find('tar') >= 0 or fname.find('tgz') >= 0:
         with tarfile.open(fname) as tf:
-            def is_within_directory(directory, target):
-                
+
+            def _is_within_directory(directory, target):
                 abs_directory = os.path.abspath(directory)
                 abs_target = os.path.abspath(target)
-            
+
                 prefix = os.path.commonprefix([abs_directory, abs_target])
-                
+
                 return prefix == abs_directory
-            
-            def safe_extract(tar, path=".", members=None, *, numeric_owner=False):
-            
+
+            def _safe_extract(tar,
+                              path=".",
+                              members=None,
+                              *,
+                              numeric_owner=False):
                 for member in tar.getmembers():
                     member_path = os.path.join(path, member.name)
-                    if not is_within_directory(path, member_path):
+                    if not _is_within_directory(path, member_path):
                         raise Exception("Attempted Path Traversal in Tar File")
-            
-                tar.extractall(path, members, numeric_owner=numeric_owner) 
-                
-            
-            safe_extract(tf, path=fpath_tmp)
+
+                tar.extractall(path, members, numeric_owner=numeric_owner)
+
+            _safe_extract(tf, path=fpath_tmp)
     elif fname.find('zip') >= 0:
         with zipfile.ZipFile(fname) as zf:
             zf.extractall(path=fpath_tmp)