Returns a list of authorisation matchers that a user is eligible for.
        This list is a combination of the provided personal matchers plus the
        matchers of any group the user is in.

def fill_auth_list_from_groups(self, auth_provider, user_groups, auth_list):
        '''
        Returns a list of authorisation matchers that a user is eligible for.
        This list is a combination of the provided personal matchers plus the
        matchers of any group the user is in.
        '''
        group_names = [item for item in auth_provider if item.endswith('%')]
        if group_names:
            for group_name in group_names:
                if group_name.rstrip("%") in user_groups:
                    for matcher in auth_provider[group_name]:
                        auth_list.append(matcher)
        return auth_list