def get_id_data_abstract_role_mappings(id_data):
    """Get the logical and physical names of the access control roles
    defined by a resource group.

    :param id_data: - Data extracted from a custom resource's physical id by
        get_data_from_custom_physical_resource_id

    :returns
        A dictionary mapping abstract role names to physical role names.
    """

    return id_data.setdefault('AbstractRoleMappings', {})