Wiggle sort II

class Solution:
    def wiggleSort(self, nums):
        if len(nums) == 1:
            return
        arr = nums[:]
        arr.sort()

        i = len(arr) - 1
        k = 1
        while i >= 0:
            nums[k] = arr[i]
            k += 2
            if k >= len(nums):
                k = 0
            i -= 1