diff --git a/product/ERP5Type/mixin/matrix.py b/product/ERP5Type/mixin/matrix.py index 02bbbecb5e0f28a0096b6f87633daea92d89c858..79fac85dbab4b28d531842d9e84652ec37ea3e3b 100644 --- a/product/ERP5Type/mixin/matrix.py +++ b/product/ERP5Type/mixin/matrix.py @@ -264,7 +264,7 @@ class Matrix(object): else: if i >= current_len: self.index[base_id][i] = PersistentMapping() - for place in self.index[base_id][i].keys(): + for place in list(self.index[base_id][i].keys()): if place not in kw[i]: del self.index[base_id][i][place]