diff --git a/tiramisu/setting.py b/tiramisu/setting.py
index f8c1d37..879656c 100644
--- a/tiramisu/setting.py
+++ b/tiramisu/setting.py
@@ -400,6 +400,15 @@ class Settings(object):
                                                          str(props)), props)
 
     def setpermissive(self, permissive, opt=None, path=None):
+        """
+        enables us to put the permissives in the storage
+        
+        :param path: the option's path 
+        :param type: str
+        :param opt: if an option object is set, the path is extracted. 
+                    it is better (faster) to set the path parameter 
+                    instead of passing a :class:`tiramisu.option.Option()` object.
+        """
         if opt is not None and path is None:
             path = self._get_opt_path(opt)
         if not isinstance(permissive, tuple):