如何在Python中单元测试随机洗牌操作？

我已经编写了代码来从 .csv 文件创建一个秘密圣诞老人列表，其中包含一组名称和相应的电子邮件。

import random
import pandas as pd

def compare(list_of_names, list_of_emails):
    zipped_lists = list(zip(list_of_emails, list_of_names))
    random.shuffle(zipped_lists)  # shuffle list of emails and names
    result = []
    shuffled_emails = [i[0] for i in zipped_lists]
    for i, _ in enumerate(shuffled_emails):
        result.append(zipped_lists[i-1][1])  # shift email relatively one position to the right
    return list(zip(result, shuffled_emails))

def main():
    names  = ["John", "Bob", "Alice"]
    emails = ["John@gmail.com", "Bob@gmail.com", "Alice@outlook.com"]

    print(compare(names,emails))

if __name__ == '__main__':
    main()

我如何对这段代码进行单元测试，因为我使用的是随机洗牌操作？我不确定如何为相同的测试用例编写测试用例。