diff --git a/resources/lib/pydrive/apiattr.py b/resources/lib/pydrive/apiattr.py
index 891956d..a97f214 100644
--- a/resources/lib/pydrive/apiattr.py
+++ b/resources/lib/pydrive/apiattr.py
@@ -19,7 +19,7 @@ class ApiAttribute(object):
     if obj.dirty.get(self.name) is not None:
       obj.dirty[self.name] = True
 
-  def __del__(self, obj):
+  def __del__(self, obj=None):
     """Delete value of this attribute."""
     del obj.attr[self.name]
     if obj.dirty.get(self.name) is not None: