changing list items

[bearophileHUGS at lycos.com]

A possibile first solution:

>>> alist = ['a','b','c','e','d','f']
>>> inf, sup = 2, 4
>>> alist[inf:sup] = ["t"] * (sup - inf)
>>> alist
['a', 'b', 't', 't', 'd', 'f']

Bye,
bearophile