python concatenate list of lists with other elements inside code example

Example 1: combining list of list to single list python

import itertools
a = [['a','b'], ['c']]
print(list(itertools.chain.from_iterable(a)))

Example 2: how to concatenate two lists in python

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

joinedlist = listone + listtwo