Calling all experts: Python Tips and Tricks

[bartonc]

I've decide to compile a bunch of your favorite tips and tricks for the Articles section.

Post your favorite tips and tricks here, in this thread, and I'll copy the best ones to a Tips and Tricks article (to be created soon).

Thanks. And have fun!

[bartonc]

It's really not hard. Nor does it need to take much time. This thread is what I have in mind.

I know that you all have it in you. So c'mon...

[ilikepython]

Ok, I don't know if this is any good, but I'll post it anyway. I wrote a function that is like a binary search on a built in list object. I was doing one of the problems from project euler and my problem was I kept repeatedly checking wether an element was in a list. When I used this function the program ran much faster. But it only works on sorted lists:

def lookfor(s, obj, start, end, stopAt = 50):
    if end - start < stopAt:
        if obj in s[start:end]:
            return True
        else:
            return False
 
    ind = start + ((end-start)/2)
    it = s[ind]
 
    if it == obj:
        return True
    elif it > obj:
        return lookfor(s, obj, start, ind)
    elif it < obj:
        return lookfor(s, obj, ind, end)
 

It can also be written as a custom list object that inherits from list and overrides the __contains__ operator. What do you guys think?