'Provide direct access to configuration fields.
If the standard configuration includes the option `\'foo\'`, then
accessing `self.foo` should be the same as `self.config[\'foo\']`.'

def __getattr__(self, key):

    if (key in self.default_config):
        return self.config.get(key, None)
    else:
        return object.__getattribute__(self, key)
