angularjs 6 python django rest框架跨域api调用问题

我已经用python 3配置了django rest框架。API在邮递员中运行良好。但是，当我通过angualar 6项目调用此api时，面临一个跨域问题。

操作系统：Mac OS

我已包含oauth2进行身份验证。与邮递员一起使用效果很好

API网址：http：//127.0.0.1：7777 / api / v1 / token /

Angular 6网站网址： http：// localhost：5000 /＃/ login

当我用angualrjs调用它时，它显示以下错误。

Mozilla：

Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at http://127.0.0.1:7777/api/v1/token/. (Reason: CORS header ‘Access-Control-Allow-Origin’ missing).

苹果浏览器：

Failed to load resource: Origin http://localhost:5000 is not allowed by Access-Control-Allow-Origin.
XMLHttpRequest cannot load http://127.0.0.1:7777/api/v1/token/. Origin http://localhost:5000 is not allowed by Access-Control-Allow-Origin.

铬：

Failed to load http://127.0.0.1:7777/api/v1/token/: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://localhost:5000' is therefore not allowed access.

python settings.py cors相关部分：

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'django.contrib.sites',
    'django.contrib.flatpages',
    'widget_tweaks',
    'rest_framework',
    'oauth2_provider',
    'corsheaders',
] + get_core_apps() 
SITE_ID = 1


ALLOWED_HOSTS = ['127.0.0.1']
CORS_ORIGIN_WHITELIST = ('localhost:5000')
CORS_ORIGIN_ALLOW_ALL = True



MIDDLEWARE_CLASSES = [

    'django.middleware.security.SecurityMiddleware',
    'corsheaders.middleware.CorsMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
]

我还安装了oscarcommerce，oauth2，django rest框架。我在系统中使用angularjs6和python 2.7配置了其他三个网站。一切都很好。仅在此python 3项目上出现此问题。