django工程目录和导入规则的错误

I generate a django project and its directory structure is like the following:
我创建了一个django工程，目录树如下：

-myproject    --__init__.py    --settings.py    --rooturls.py    --dbUtils.py    --app1        ---__init__.py        ---views.py        ---urls.py    --app2        ---__init__.py        ---views.py        ---urls.py

I want to import dbUtils in my apps , so I configure in my settings.py:
我要导入 dbUtils，所以配置 settings.py：

PROJECT_ROOT = os.path.dirname(__file__)sys.path.insert(0, PROJECT_ROOT)

However, the program still can't find the moudle.
但是工程里还是找不到这个moudle。