list printing brackets within the output

here is my code

old_lists = [['one', 'two', ['three', 'four', 'five']], 
['six', 'seven', ['eight', 'nine', 'ten']], 
['eleven', 'twelve', ['thirteen', 'fourteen', 'fifteen']]]

new_list = []

for i, j, k in old_lists:
    new_list.append(i, j, k)

print(new_list)

I am getting this output

one two ['three', 'four', 'five']
six seven ['eight', 'nine', 'ten']
eleven twelve ['thirteen', 'fourteen', 'fifteen']

I would like the below output

['one', 'two', 'three', 'four', 'five']
['six', 'seven', 'eight', 'nine', 'ten']
['eleven', 'twelve', 'thirteen', 'fourteen', 'fifteen']

Answer

new_list = []

for i, j, k in old_lists:
    new_list.append( [i,j]+k )

print(new_list)

Or even better:

new_list = [ [i,j]+k for i,j,k in old_lists ]