Using .join() in Python

Question

Very simple and quick question. Take this list for example:

a = ['hello1', 'hello2', 'hello3']
','.join(a)

I would like to have 'and' instead of a comma before the last element of the list. So I would get:

hello 1, hello 2 and hello 3

instead of....

hello 1, hello 2, hello 3

Is there a way to accomplish this using .join()? I know I can just type it in the list for a simple example like this, but the list I need in my actual program comes from user input.

Answer 1

In essence, you want to manipulate the two parts of the list separately, the first consisting of everything except the last string, and the other consisting of just the last one.

def my_func(lst):
    return ', '.join(lst[:-1])+' and '+lst[-1]

or using a lambda:

f = lambda x: ', '.join(x[:-1]) + ' and '+x[-1]

or if you just want it run once:

result = ', '.join(a[:-1]) + ' and ' + a[-1]