Halve until under

A price is cut in half repeatedly until it is below limit. Write halvings(price, limit) that returns how many halvings that takes. If the price is already below the limit, return 0.

halvings(100, 10)  ->  4     (100 -> 50 -> 25 -> 12.5 -> 6.25)
halvings(5, 10)    ->  0

def halvings(price, limit):
    ...