human
Solve the following python programming problem given the following code:
def _cbTestReflector(self, parent) : 
    test_values = { 
        
} 
    inserts = [] 
    child_values = { 
        
} 
    for i in range (0, self.num_iterations) : 
        row = ChildRow () 
        row.assignKeyAttr ('childId', i) 
        values = self.randomizeRow (row) 
        values ['test_key'] = row.test_key = 'first' 
        child_values [i] = values 
        inserts.append (self.reflector.insertRow (row)) 
        row = None 
d = defer.gatherResults (inserts) 
    values = [None] 
    def _loadObjects(_) : 
        d = self.reflector.loadObjectsFrom (childTableName, parentRow = parent) 
        return d.addCallback (self.gotData) 
def _checkLoadObjects(_) : 
        self.failUnless ((len (self.data) == self.num_iterations), 'no rows on query') 
        self.failUnless ((len (parent.childRows) == self.num_iterations), ('did not load child rows: %d' % len (parent.childRows))) 
        for child in parent.childRows : 
            self.failUnless (rowMatches (child, child_values [child.childId]), ('child %d does not match' % child.childId)) 
def _checkLoadObjects2(_) : 
        self.failUnless ((len (self.data) == self.num_iterations), 'no rows on query') 
        self.failUnless ((len (parent.childRows) == self.num_iterations), ('child rows added twice!: %d' % len (parent.childRows))) 
def _changeParent(_) : 
        values [0] = self.randomizeRow (parent) 
        return self.reflector.updateRow (parent) 
def _loadBack(_) : 
        whereClause = [('key_string', EQUAL, 'first')] 
        d = self.reflector.loadObjectsFrom (tableName, whereClause = whereClause) 
        return d.addCallback (self.gotData) 
def _checkLoadBack(_) : 
        self.failUnless ((len (self.data) == 1), 'no row') 
        parent = self.data [0] 
        self.failUnless (rowMatches (parent, values [0]), 'no match') 
        test_values [parent.key_string] = values [0] 
        parent = None 
def _saveMoreTestRows(_) : 
        ds = [] 
        for i in range (0, self.num_iterations) : 
            row = TestRow () 
    ...
    
    Given the code above, what is a proper replacement for <MASK>? Choose among: _cbChangeRows, _checkLoadBack, _checkRowsDeleted, self, _changeParent, _checkRowsBack, _changeRows, _checkLoadObjects, _loadObjects, i, _deleteRows, values, test_values, child_values, _loadBack, d, _loadRowsBack, row, inserts, _saveMoreTestRows, parent
assistant
#Here is a proper replacement for <MASK>.
def _checkLoadObjects2(