OperationalError at /admin/login/
FATAL:  password authentication failed for user "usr"
FATAL:  password authentication failed for user "usr"
Request Method: POST
Request URL:    https://www.***.com/admin/login/?next=/admin/
Django Version: 1.11
Exception Type: OperationalError
Exception Value:
FATAL:  password authentication failed for user "usr"
FATAL:  password authentication failed for user "usr"
Exception Location: /***/lib/python3.5/site-packages/psycopg2/__init__.py in connect, line 130
Python Executable:  ***
Python Version: 3.5.2

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.postgresql',
        'NAME': 'db',
        'USER': 'usr',
        'PASSWORD': os.environ["DB_PASSWORD"],
        'HOST': 'localhost',
    }
}

export DB_PASS="*******"

export SECRET_KEY="******************************"

[Unit]
Description=gunicorn daemon
After=network.target

[Service]
User=*****
Environment=SECRET_KEY="**********************************"
Environment=DB_PASS="***********"
Group=www-data
WorkingDirectory=/home/***/vp/vp/
ExecStart=/home/***/vp/vpenv/bin/gunicorn --workers 3 --bind unix:/home/***/v$


[Install]
WantedBy=multi-user.target

List of databases
   Name    |  Owner   | Encoding |   Collate   |    Ctype    |   Access privileges   |  Size   | Tablespace |                Description
-----------+----------+----------+-------------+-------------+-----------------------+---------+------------+--------------------------------------------
 postgres  | postgres | UTF8     | en_US.UTF-8 | en_US.UTF-8 |                       | 6992 kB | pg_default | default administrative connection database
 template0 | postgres | UTF8     | en_US.UTF-8 | en_US.UTF-8 | =c/postgres          +| 6857 kB | pg_default | unmodifiable empty database
           |          |          |             |             | postgres=CTc/postgres |         |            |
 template1 | postgres | UTF8     | en_US.UTF-8 | en_US.UTF-8 | =c/postgres          +| 6857 kB | pg_default | default template for new databases
           |          |          |             |             | postgres=CTc/postgres |         |            |
 db      | postgres | UTF8     | en_US.UTF-8 | en_US.UTF-8 | =Tc/postgres         +| 7600 kB | pg_default |
           |          |          |             |             | postgres=CTc/postgres+|         |            |
           |          |          |             |             | vpusr=CTc/postgres    |         |            |

List of roles
 Role name |                         Attributes                         | Member of
-----------+------------------------------------------------------------+-----------
 postgres  | Superuser, Create role, Create DB, Replication, Bypass RLS | {}
 vp        |                                                            | {}
 usr     |                                                            | {}

[Service]
...
EnvironmentFile=/pathto/somefilewith_secrets

[Service]
...
Environment="DATABASE_PASSWORD=mypassword"

/path-to-virtualenv/gunicorn
    --bind unix:/path_to_myproject.sock myproject.wsgi:application
    -e DATABASE_PASSWORD=mypassword -e my_var2=value2

> DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.postgresql_psycopg2',
        'NAME': 'db',
        'USER': 'usr',
        'PASSWORD': os.environ.get("DB_PASSWORD"),
        'HOST': 'localhost',
        'PORT': '',
    }