Google | Sort an Array

from collections import Counter
class Solution:
    def sortArray(self, nums: List[int]) -> List[int]:
        def mergeSort(nums):
            if len(nums) > 1: 
                mid = len(nums)//2
                L = nums[:mid] 
                R = nums[mid:] 

                mergeSort(L)
                mergeSort(R)

                i = j = k = 0

                while i < len(L) and j < len(R): 
                    if L[i] < R[j]: 
                        nums[k] = L[i] 
                        i+=1
                    else: 
                        nums[k] = R[j] 
                        j+=1
                    k+=1
    
                while i < len(L): 
                    nums[k] = L[i] 
                    i+=1
                    k+=1

                while j < len(R): 
                    nums[k] = R[j] 
                    j+=1
                    k+=1
        mergeSort(nums)
        return nums