diff --git a/clone.py b/clone.py
index 36c6bb1..67ee3f7 100644
--- a/clone.py
+++ b/clone.py
@@ -5,6 +5,7 @@ import logging
 import string
 import hashlib
 import time
+import shutil
 
 
 class Cloner:
@@ -34,8 +35,7 @@ class Cloner:
                 targetFileContent = targetFile.read()
                 realHash = hashlib.md5(targetFileContent).hexdigest()
                 if realHash != cloneHashFileContent:
-                    os.system('cp {backup} {real}'.format(
-                        backup=cloneFileName, real=targetFileName))
+                    shutil.copyfile(cloneFileName, targetFileName)
                     logging.warning(
                         '{file} failed check, restoring...'.format(file=targetFileName))
                 else:
@@ -43,8 +43,7 @@ class Cloner:
         else:
             logging.warning(
                 '{file} is a new file, added to backup dir'.format(file=targetFileName))
-            os.system('cp {real} {clone}'.format(
-                real=targetFileName, clone=cloneFileName))
+            shutil.copyfile(targetFileName, cloneFileName)
             with open(cloneHashFileName, 'w') as cloneHashFile, open(targetFileName, 'rb') as targetFile:
                 targetFileContent = targetFile.read()
                 cloneHashFile.write(hashlib.md5(targetFileContent).hexdigest())