How to slice a list of tuples in python?

Your solution looks like the most pythonic to me; you could also do

tuples = [(0,'a'), (1,'b'), (2,'c')]
print zip(*tuples)[0]

... but to me that's too "clever", and the list comprehension version is much clearer.

You can use * unpacking with zip().

>>> l = [(0,'a'), (1,'b'), (2,'c')]
>>> for item in zip(*l)[0]:
...     print item,
...
0 1 2

For Python 3, zip() doesn't produce a list automatically, so you would either have to send the zip object to list() or use next(iter()) or something:

>>> l = [(0,'a'), (1,'b'), (2,'c')]
>>> print(*next(iter(zip(*l))))
0 1 2

But yours is already perfectly fine.

You could convert it to a numpy array.

import numpy as np
L = [(0,'a'), (1,'b'), (2,'c')]
a = np.array(L)
a[:,0]