Python: extend() Append Elements of a List to a List

When you append a list to a list by using append() method, you’ll see your list is going to be appended as a list: 1>>>l=["a"] 2>>>l2=["a", "b"] 3>>>l.append(l2) 4>>>l 5['a', ['a', 'b']] If you want to append elements of the list directly without creating nested lists, use extend() method: 1>>>l=["a"] 2>>>l2=["a", "b"] 3>>>l.extend(l2) 4>>>l 5['a', 'a', 'b']