python代码写出给定数组a={7,2,1,6,5,4,3,8},使用合并排序算法将数组里面的元素进行从小到大的排序。

下面是使用归并排序算法将数组a从小到大排序的Python代码：

def merge_sort(arr):
    if len(arr) <= 1:
        return arr
    mid = len(arr) // 2
    left = merge_sort(arr[:mid])
    right = merge_sort(arr[mid:])
    return merge(left, right)

def merge(left, right):
    result = []
    i, j = 0, 0
    while i < len(left) and j < len(right):
        if left[i] < right[j]:
            result.append(left[i])
            i += 1
        else:
            result.append(right[j])
            j += 1
    result += left[i:]
    result += right[j:]
    return result

a = [7, 2, 1, 6, 5, 4, 3, 8]
result = merge_sort(a)
print(result)

输出结果为：[1, 2, 3, 4, 5, 6, 7, 8]