how to combine two elements in list python code example

Example 1: combine all items in a list python

>> a = ['a', 'b', 'c']
>> res = "".join(a)
>> print(res)
abc

Example 2: merge lists in list python

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