efficient matching of elements a list

[Josiah Carlson]

>>Suppose I have a lists of tuples
>>A_LIST=[(1,6,7),(7,4,2),(7,9,2),(1,5,5),(1,1,1)]
>>and an int
>>i=1
>>What is the fastest way in python to get out all the tuples from the
>>list whose first element  is equal to i?
> 
> 
> t = [x for x in A_LIST if x[0] == i]

Before list comprehensions, we had to do it all with filter...
t = filter(lambda x:x[0]==i, A_LIST)

List comprehension seem to be around 33% faster.  Long live list 
comprehensions.

  - Josiah