The way to attach behavior to keys with with bindings. For example, assuming you have a canvas widget where you are doing your animations. If you want the up arrow key to call a function such as to change the direction of the paddle, you would create a binding like this:
def move_up(event):
<put your "move up" code here>
the_canvas.bind("<Up>", move_up)
This will cause the move_up
function to be called every time the user presses the "up" arrow key.
There are many places on the internet to learn about bindings. Tkdocs.com is one such site. A tutorial on bindings can be found here: http://www.tkdocs.com/tutorial/concepts.html#events