Animation plays while button held down

This might be a fun little challenge for you guys. How would I make it so an animation plays while I have a button held down, stops when I release it, BUT resumes when I hold it down again. So lets just say its a 5 step animation, and I hold it down for 2 steps, 1 and 2. When I release it, it stops. When I hold it down again, it resumes from 3, as oppose to starting again

 

If you are using the Animator component simply change the value of Animator.speed to 0 when the button is not pressed and 1 when it pressed.