Update updater to handle venv folders

cps/updater.py

@@ -193,7 +193,12 @@ class Updater(threading.Thread):
         exclude = (
             os.sep + 'app.db', os.sep + 'calibre-web.log1', os.sep + 'calibre-web.log2', os.sep + 'gdrive.db',
             os.sep + 'vendor', os.sep + 'calibre-web.log', os.sep + '.git', os.sep + 'client_secrets.json',
-            os.sep + 'gdrive_credentials', os.sep + 'settings.yaml')
+            os.sep + 'gdrive_credentials', os.sep + 'settings.yaml', os.sep + 'venv', os.sep + 'virtualenv',
+            os.sep + 'access.log', os.sep + 'access.log1', os.sep + 'access.log2',
+        )
+        additional_path = self.is_venv()
+        if additional_path:
+            exclude = exclude + (additional_path)
         for root, dirs, files in os.walk(destination, topdown=True):
             for name in files:
                 old_list.append(os.path.join(root, name).replace(destination, ''))
@@ -229,6 +234,12 @@ class Updater(threading.Thread):
                     logger.debug("Could not remove: %s", item_path)
         shutil.rmtree(source, ignore_errors=True)
 
+    def is_venv(self):
+        if (hasattr(sys, 'real_prefix')) or (hasattr(sys, 'base_prefix') and sys.base_prefix != sys.prefix):
+            return os.sep + os.path.relpath(sys.prefix,constants.BASE_DIR)
+        else:
+            return False
+
     @classmethod
     def _nightly_version_info(cls):
         if is_sha1(constants.NIGHTLY_VERSION[0]) and len(constants.NIGHTLY_VERSION[1]) > 0: