Write a function that takes a list of at least four elements as an argument and returns a list of the middle two or three elements in reverse order.
def reverse_middle(lst):
    l = len(lst)
    return lst[(l+1)//2:(l//2)-2:-1] 
def reverse_middle(lst):
    l = len(lst)
    return lst[(l+1)//2:(l//2)-2:-1] 