Need help with making use of Pluck in Python

Question

Hi all, today was a good day. I finally started researching on the underscore.js module today and I could find out a couple of stuff about it.
 

For one, it is a library which supports javascript. This basically adds to the functional aspects you get to work within Python as well. So this method is called pluck.

Now consider this - Let us say I have a requirement wherein I have to pluck out a specific attribute, this is what I'd do:

users = [{
    "name" : "Edureka",
    "uid" : "744639207"
},
{
    "name" : "Anirudh",
    "uid" : "3"
}]
uids = map(lambda x:x["uid"], users)

If the shorthand for the underscore is present somewhere in the same Python code, would the following piece of code be possible?

Code:

uids = pluck(users, "uid")

All help appreciated!

Answer 1

Hi, good question. Easy solution to be honest - Make sure you use of a list comprehension in all of the functions that make use and keep track of the uids.

Check out this following piece of code:

ids = map(operator.itemgetter("uid"), users)
foo(uids)

Instead of this piece of code, make use of this below code and it will solve the issue:

foo([x["uid"] for x in users])

Let us say your only requirement is that you need the uids as an iteration variable, then make sure that you don't need a list. 

So what is the alternative? Use a generator. How do you do this?

It is very simple - Replace [] with () and you're good to go.

Hope this helped!