You cannot extend the built-in types, no.
You can only subclass them, but that only helps if you have full control over the creating and use.
Domanda
I'm just curious is it possible to create function in Python which work on any sequence. For example:
>>> def head(self):
>>> return self[0]
>>>
>>> a = [1, 2, 3]
>>> a.head()
1
>>> xrange(10).head()
0
Soluzione
You cannot extend the built-in types, no.
You can only subclass them, but that only helps if you have full control over the creating and use.