How do I concatenate two lists in Python?

Question

How do I concatenate two lists in Python?

Example:

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

Expected outcome:

>&g         


        

Answer 1

list(set(listone) | set(listtwo))

The above code, does not preserve order, removes duplicate from each list (but not from the concatenated list)