stylistic - usually better to avoid a backslash whenever possible. I'd rather it be written something like this:

        direction, secrule = self._get_security_group_rule_object(context, 
                                                                  rule)
or

        direction, secrule = self._get_security_group_rule_object(
             context, rule)

Also, the parens aren't necessary around the tuple, though that's less important.