Which function for "pressed" on keyboard? How to code in python for BGE as detect "pressed" on keyboard ?  

Example, AKEY to move x coordinate but when press A key it don't move infinitely however it does pressed...

How to solve it? Thanks
I found a link on blender.org here: https://docs.blender.org/api/blender_python_api_2_59_0/bge.events.html It covers keypresses using bge.events