Request for python version of AesKeyRing

## Problem

- Our producer is java based which uses [AesKeyRIng](https://github.com/aws/amazon-s3-encryption-client-java/blob/main/src/main/java/software/amazon/encryption/s3/materials/AesKeyring.java) with `S3EncryptionClient` to encrypt data.
- But our consumer side requiring to decrypt data is in Python. However, Python does not contain `AesKeyRing` equivalent.

We use AesKeyRing to generate DataKeys with our own WrappingKey generator , which is NOT KMS. This is a hard requirement for us and `AesKeyRing` unblocked us in java. However, we are blocked in python as its not available.

I wanted to raise this request to the team to implement a python version of `AesKeyRing` , so that we can be unblocked.

首先阅读链接的 Java AesKeyring.java 实现和 S3EncryptionClient 的用法，然后跟踪 Python package 中现有的加密和 keyring 入口点。当 Python 的 AesKeyRing 等效实现能够使用调用方提供的非 KMS wrapping-key 生成器生成数据密钥，并解密 Java client 生成的数据时，即表示完成。

由索引模型根据 Issue 内容生成。