How long does it take to 'learn machine learning'? I'm pretty sure I know some about it. I can certainly apply some basic algorithms and there's no shortage of

How long does it take to 'learn machine learning'? I'm pretty sure I know some about it. I can certainly apply some basic algorithms and there's no shortage of info about lots of variations on the basics I do already know. So what am I missing? How much would I have to learn to be able to claim, per your unstated standard, that I've 'learned machine learning'?