启用Django服务时报错：django.core.exceptions.ImproperlyConfigured: The INSTALLED_APPS setting must be a list or a tuple.

启用Django服务时（Python manage.py runserver），报错：django.core.exceptions.ImproperlyConfigured: The INSTALLED_APPS setting must be a list or a tuple.

原因：

Django项目XXX目录下setting.py文件中

INSTALLED_APPS = [

    'django.contrib.admin',

    'django.contrib.auth',

    'django.contrib.contenttypes',

    'django.contrib.sessions',

    'django.contrib.messages',

    'django.contrib.staticfiles',

]

列表[]括号，被误变更为{}导致的，这里可用（）、[]，不能用{}