def mailing_list():
    """ RESTful CRUD controller """

    tablename = "pr_group"
    table = s3db[tablename]

    # Only groups with a group_type of 5
    s3.filter = (table.group_type == 5)
    table.group_type.writable = False
    table.group_type.readable = False
    table.name.label = T("Mailing List Name")
    s3.crud_strings[tablename] = s3.pr_mailing_list_crud_strings

    # define the list_fields
    list_fields = s3db.configure(tablename,
                                 list_fields = ["id",
                                                "name",
                                                "description",
                                                ])
    # Components
    _rheader = s3db.pr_rheader
    _tabs = [(T("Organization"), "organisation/"),
             (T("Mailing List Details"), None),
             ]
    if len(request.args) < 0:
        _tabs.append((T("Members"), "group_membership"))
    if "viewing" in request.vars:
        tablename, record_id = request.vars.viewing.rsplit(".", 1)
        if tablename == "org_organisation":
            table = s3db[tablename]
            _rheader = s3db.org_rheader
            _tabs = []
    s3db.add_components("pr_group", pr_group_membership="group_id")

    rheader = lambda r: _rheader(r, tabs = _tabs)
    return s3_rest_controller("pr",
                              "group",
                              rheader=rheader)

# -----------------------------------------------------------------------------
dataset/ETHPy150Open sahana/eden/controllers/org.py/mailing_list/operator `>` -> `<`