twilio/flask-restful — pull request #185 by papaeye (2014-01-23 08:54:54+00:00)
Title: Support callable default

This is useful when the default value comes from current_app.config like this:

```python
parser = reqparse.RequestParser()
parser.add_argument('foo', type=int,
default=lambda: current_app.config['DEFAULT_FOO'])
```