def create_missing(self):
        """Possibly set several extra instance attributes.

        If ``onthefly_register`` is set and is true, set the following instance
        attributes:

        * account_password
        * account_firstname
        * account_lastname
        * attr_login
        * attr_mail

        """
        super(AuthSourceLDAP, self).create_missing()
        if getattr(self, 'onthefly_register', False) is True:
            for field in (
                    'account_password',
                    'attr_firstname',
                    'attr_lastname',
                    'attr_login',
                    'attr_mail'):
                if not hasattr(self, field):
                    setattr(self, field, self._fields[field].gen_value())
Possibly set several extra instance attributes.

        If ``onthefly_register`` is set and is true, set the following instance
        attributes:

        * account_password
        * account_firstname
        * account_lastname
        * attr_login
        * attr_mail