Remove some leftover attribute[number]

AddCommand.py

@@ -49,9 +49,9 @@ class AddCommand(Command.Command):
                     continue
 
                 if p_tag == 'after':
-                    self.todolist.add_dependency(self.todo.attributes['number'], value)
+                    self.todolist.add_dependency(self.todolist.number(self.todo), value)
                 elif p_tag == 'before' or p_tag == 'partof':
-                    self.todolist.add_dependency(value, self.todo.attributes['number'])
+                    self.todolist.add_dependency(value, self.todolist.number(self.todo))
 
                 self.todo.remove_tag(p_tag, raw_value)
 

ArchiveCommand.py

@@ -9,4 +9,4 @@ class ArchiveCommand(Command.Command):
     def execute(self):
         for todo in [t for t in self.todolist.todos() if t.is_completed()]:
             self.archive.add_todo(todo)
-            self.todolist.delete(todo.attributes['number'])
+            self.todolist.delete(self.todolist.number(todo))

Filter.py

@@ -69,7 +69,8 @@ class DependencyFilter(Filter):
         """
         Returns True when there are no children that are uncompleted yet.
         """
-        children = self.todolist.children(p_todo.attributes['number'])
+        number = self.todolist.number(p_todo)
+        children = self.todolist.children(number)
         uncompleted = [todo for todo in children if not todo.is_completed()]
 
         return not uncompleted