How to map 2 lists with comparison in python

Question

I have a list of objects of say foos. I have a loop for creating a new list.

foo1 = {id:1,location:2}
for e.g. foos = [foo1,foo2,foo3]

Now I want to create a new list based on location.

new_list = []
for foo in foos:
  if foo.location==2:
      new_list.append(foo)

What I want to know is there any way in which I can do something like this

new_list = []
new_list = map(if foo.location ==2,foos) // this is wrong code but is something like this possible. ?

Can I use map function here ? if yes how ?

Answer 1

Sure thing you can do it with function. You can use the filter builtin function:

new_list = filter(lambda foo: foo.location == 2, foos)

But the more general and "pythonic" way is to use list comprehensions

new_list = [foo for foo in foos if foo.location == 2]

Answer 2

List comprehension seems to be what you want to use:

new_list = [foo for foo in foos if foo.location == 2]

map is good when you want to apply a function to every item in a list (or any iterable) and get a list of equal length (or an iterator in Python3) as a result. It can't "skip" items based on some condition.