python - 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。