def METHOD_NAME():
    a = relay.TypeVar("a")
    b = relay.TypeVar("b")
    c = relay.TypeVar("c")
    ft1 = relay.FuncType([b], c, [a])
    assert_vars_match(all_type_vars(ft1), [a, b, c])
    ft2 = relay.FuncType([], relay.TupleType([a, b, c]), [])
    assert_vars_match(all_type_vars(ft2), [a, b, c])
    w = relay.Var("w")
    x = relay.Var("x", a)
    y = relay.Var("y", b)
    z = relay.Var("z", c)
    f1 = relay.Function([x], y, b, [a])
    assert_vars_match(all_type_vars(f1), [a, b])
    f2 = relay.Function([x], relay.Let(y, x, z))
    assert_vars_match(all_type_vars(f2), [a, b, c])
    f3 = relay.Function([], relay.Tuple([x, y, z]), ret_type=relay.TupleType([a, b, c]))
    assert_vars_match(all_type_vars(f3), [a, b, c])
    f4 = relay.Function([w], relay.Tuple([]), type_params=[a, b, c])
    assert_vars_match(all_type_vars(f4), [a, b, c])
    f5 = relay.Function([w], w)
    assert len(all_type_vars(f5)) == 0