page 43 (Chapter 2 , this seems serious technical error on methods of tuples)

[georgiosdoumas]

At the end of the page 43 this is mentioned :
(unless you need methods such as index and count, which tuples don’t have)

But I created a tuple and I could call those 2 methods ( i have Python 3.6):
>>> mynumtuple = (10,20,30)
>>> len(mynumtuple)
3
>>> mynumtuple.index(30)
2