Python: Concatenating sublists between different lists -

i have 2 lists of lists, of equal length, this:

lsta = [[1,4,5,6],[4,5],[5,6],[],[],[],[],[]] lstb = [[7,8],[4,5],[],[],[],[2,7,8],[7,8],[6,7]]

and want concatenate sublists @ each index position such make single sublist, this:

 newlst = [[1,4,5,6,7,8],[4,5],[5,6],[],[],[2,7,8],[7,8],[6,7]]

ideally, new sublists remove duplicates (like in newlst[1]). converted integers strings, , attempted this:

for in range(len(lsta)):     c = [item + item item in stra[i], strb[i]]

but adds each item each list before adding other list, resulting in this:

failedlst = [[["1","4","5","6","1","4","5","6"],["7","8","7","8"]],[["4","5","4","5"],["4","5","4","5"]]...etc]

and still doesn't join 2 sublists, makes new sublist of 2 sublists. appeciated!

making list concatenating items in parallel simple, using list comprehension in combination zip function.

newlst = [x+y x,y in zip(lsta, lstb)]

if want remove duplicates, can use set. if want put items in order in list, can use sorted.

in combination, this:

newlst = [sorted(set(x+y)) x,y in zip(lsta, lstb)]

If code