在Python中，结合对称加密和非对称加密可以充分利用两者的优势:对称加密速度快，适合加密大量数据，非对称加密安全性高，适合加密对称密钥。这种组合方式常用于安全通信场景。
典型案例:使用RSA加密AES密钥，然后用AES加密数据
from Crypto.Cipher import AES, PKCS1_OAEP
from Crypto.PublicKey import RSA
from Crypto.Random import get_random_bytes
import base64# 生成RSA密钥对
rsa_key = RSA.generate(2048)
private_key = rsa_key.export_key()
public_key = rsa_key.publickey().export_key()# 生成AES对称密钥
aes_key = get_random_bytes(16) # AES-128，密钥长度16字节# 用RSA公钥加密AES密钥
rsa_cipher = PKCS1_OAEP.new(RSA.import_key(public_key))
encrypted_aes_key = rsa_cipher.encrypt(aes_key)# 用AES密钥加密数据
data = b"这是需要加密的大量数据"
aes_cipher = AES.new(aes_key, AES.MODE_EAX)
ciphertext, tag = aes_cipher.encrypt_and_digest(data)# 解密过程：先用RSA私钥解出AES密钥，再用AES密钥解出数据
rsa_decipher = PKCS1_OAEP.new(RSA.import_key(private_key))
decrypted_aes_key = rsa_decipher.decrypt(encrypted_aes_key)aes_decipher = AES.new(decrypted_aes_key, AES.MODE_EAX, nonce=aes_cipher.nonce)
decrypted_data = aes_decipher.decrypt_and_verify(ciphertext, tag)print("解密后的数据：", decrypted_data.decode('utf-8'))