Please teach me how to play keyframeSequences like animations!?

I really need to know how to play a KeyframeSequence like an Animation!

print("PLEASE HELP NOW NOW NOW NOW (if u know how to)")
warn("I mean it >:(")

But seriously, I need a lot of help with this.

ANYONE KNOW?

oh, and I also need to know how to do it using a script, not like a looped checkbox or anything if u can do that in any way. i need it in script form