Creating a Python list from a list of tuples

Question

If I have, for example, a list of tuples such as

a = [(1,2)] * 4

how would I create a list of the first element of each tuple? That is,

Answer 1

Two alternatives to phihag's list comprehension:

[x for x, y in a]

from operator import itemgetter
map(itemgetter(0), a)