add multiple lists in python for loop code example

Example 1: python merge two list

listone = [1,2,3]
listtwo = [4,5,6]

joinedlist = listone + listtwo

Example 2: join lists python

first_list = ["1", "2"]
second_list = ["3", "4"]

# Multiple ways to do this:
first_list += second_list
first_list = first_list + second_list
first_list.extend(second_list)