human
Solve the following python programming problem given the following code:
def create_tree(self, persistent_config, temp_config) : 
    def create_item(parent, obj, parent_obj, name, temp_obj, temp_parent_obj) : 
        item = QConfigurationTreeWidgetItem (parent, obj, parent_obj, name, temp_obj, temp_parent_obj) 
        if isinstance (obj, ConfigurationObject) : 
            for key in sorted (obj.keys ()) : 
                create_item (item, getattr (obj, key), obj, key, getattr (temp_obj, key), temp_obj) 
self.disconnect (self, QtCore.SIGNAL ('itemChanged(QTreeWidgetItem *, int)'), persistent_config.change_configuration) 
    self.clear () 
    self._configuration = persistent_config 
    self._temp_configuration = temp_config 
    create_item (self, self._configuration, None, 'configuration', self._temp_configuration, None) 
    self.expandAll () 
    self.resizeColumnToContents (0) 
    self.connect (self, QtCore.SIGNAL ('itemChanged(QTreeWidgetItem *, int)'), self.change_configuration) 

    
    

    Fix the buggy line: self.disconnect (self, QtCore.SIGNAL ('itemChanged(QTreeWidgetItem *, int)'), persistent_config.change_configuration)
assistant
#Here is Python code to fix the buggy line: self.

self.disconnect (self, QtCore.SIGNAL ('itemChanged(QTreeWidgetItem *, int)'), self.change_configuration)