You can change which python you're using with your IDE, if you've already downloaded python 3.x it shouldn't be too hard to switch. But your script works fine on python 3.x, I would just change
print ("your name is" + input_variable)
to
print ("your name is", input_variable)
Because with the comma it prints with a whitespace in between your name is
and whatever the user inputted. AND: if you're using 2.7 just use raw_input
instead of input.