实例学习Ansible：幂等性

知识点：
主要采用具备幂等性的Ansible模块设计，在多个执行过程中能够保持一致的结果，并尽量不使用不具备这一特性的组件

什么是幂等性

幂等性（Idempotency）：
Idempotency is a fundamental concept in both mathematics and computer science. In mathematics, idempotence refers to an operation where repeated execution consistently yields the same result. Idempotent functions or operations maintain this property, ensuring that their outcomes remain unchanged regardless of how many times they are applied.

Idempotency can be formally defined as a property of an operation or function where applying it multiple times has the same effect as applying it on