None shown in output

[Benjamin Kaplan]

On Thu, Jun 21, 2012 at 8:42 PM, Xander Solis <xrsolis at gmail.com> wrote:
> Hello Python list,
>
> Noob here with a newbie question. I'm reading and working on the exercise of
> the book, Learn Python the Hard way 2.0. When I use this code, I get "None"
> on the output. My question is why does this happen?
>
> def get_numbers(first_num, second_num, operator):
>
>     if operator == 'add':
>         print first_num + second_num
>     elif operator == 'minus':
>         print first_num - second_num
>     elif operator == 'divide':
>         print first_num / second_num
>     elif operator == 'multiply':
>         print first_num * second_num
>
> print "%r" % (get_numbers(1, 2, 'minus'))
> print "%r" % (get_numbers(1+3, 2+9, 'add'))
> print "%r" % (get_numbers(10, 2, 'divide'))
>
> Output:
>
> C:\code\python>ex19.py
> -1
> None
> 15
> None
> 5
> None
> 7.5
>
> --
>
> Thanks in advance for your help.
>
> Regards,
>
> Xander
>

printing something just writes the value to th