Cannot connect using postgres.
Install psycopg2 yo. Thanks bro.
Cannot connect using postgres.

```
db = PostgresqlDatabase('extra', user='extra',
                                          password='GBQ9x%@S', host='localhost')

def connect():
    try:
        db._connect()
    except BaseException as e:
        return e
connect()
```

_AttributeError("'NoneType' object has no attribute 'connect'")_

