#!/usr/bin/env python
# coding: utf-8
from itertools import chain
a = [1, 2, 3, 4]
b = ['x', 'y', 'z']

for x in chain(a, b):
    print(x)

# Various working sets of items
active_items = set()
inactive_items = set()

# Iterate over all items
for item in chain(active_items, inactive_items):
    # Process item

for item in active_items:
 # Process item
 
    
for item in inactive_items:
 # Process item



