How to use default database in django testing

Now I want to test API using my default database as I need too many data first to mock the request so I don't want to setup test database

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.postgresql_psycopg2',
        'NAME': 'bills_db',
        'USER': 'root',
        'PASSWORD': '****',
    }
}

How can I use it ?