sum from List, checksum(0, [2,4,8], 6) -> True, checksum(0, [2,4,8], 15) -> False

checksum.py

from typing import List

def checksum(acc: int, lst: List[int], exist_total: int)-> bool:
    sorted_nums = sorted(lst)
    return checksum_rec(sorted_nums, exist_total, exist_total)

def checksum_rec(nums: List, exist_total: int, orig_total: int)->int:
    if len(nums) == 0 and exist_total > 0:
        return False
    else:
        top_value = nums.pop()

        # handles top value larger than original total
        if orig_total < top_value:
            return checksum_rec(nums, orig_total, orig_total)

        temp = exist_total-top_value
        
        if temp in nums:
            return True

        # handle minus from substraction
        if temp < 0:
            nums.append(top_value)
            return checksum_rec(nums, orig_total, orig_total)

        if temp == 0:
            return True

        return checksum_rec(nums, temp, orig_total)