>>> T  
(1, 2, 3, 4)  
>>> T[0] = 22   
Traceback (most recent call last):  
  File "<pyshell#129>", line 1, in <module>  
    T[0] = 22  
TypeError: 'tuple' object does not support item assignment 

>>> T = (1,2,3,4)  
>>> (22,) + T[1:]  
(22, 2, 3, 4)