Answers for "concat a list in python"

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)

python concatenate list of lists

x = [["a","b"], ["c"]]

result = sum(x, [])

merge lists in list python

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