An elegant and fast way to consecutively iterate over two or more containers in Python?

Question

I have three collection.deques and what I need to do is to iterate over each of them and perform the same action:

for obj in deque1:  
    some_action(obj)           


        

Answer 1

Accepts a bunch of iterables, and yields the contents for each of them in sequence.

def XXX(*lists):
   for aList in lists:
      for item in aList:
         yield item



l1 = [1, 2, 3, 4]
l2 = ['a', 'b', 'c']
l3 = [1.0, 1.1, 1.2]

for item in XXX(l1, l2, l3):
   print item

1
2
3
4
a
b
c
1.0
1.1
1.2