Updating dictionary with tuple

[Mark17]

I'm trying to understand the update method by adding a tuple to a dictionary. Can someone please the Traceback here? I was able to add a list of two tuples but not this one. Thanks!

>>> d
{1: 'one', 2: 'two', 'y': 6}
>>> tuplist2
(4, 9)
>>> d.update(tuplist2)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: cannot convert dictionary update sequence element #0 to a sequence
>>>