用python帮我写一个RSA加密算法

当然可以，RSA是一种非对称加密算法，Python中有一个名为`cryptography`的库可以方便地实现它。下面是一个简单的RSA加密和解密的例子：

from cryptography.hazmat.primitives import hashes
from cryptography.hazmat.primitives.asymmetric import rsa, padding
from cryptography.hazmat.primitives import serialization
from cryptography.exceptions import InvalidSignature

# RSA密钥生成
def generate_rsa_key_pair():
    private_key = rsa.generate_private_key(
        public_exponent=65537,
        key_size=2048
    )
    public_key = private_key.public_key()
    return private_key, public_key

# 加密函数
def encrypt_data(plaintext, public_key):
    ciphertext = public_key.encrypt(
        plaintext.encode(),
        padding.OAEP(
            mgf=padding.MGF1(algorithm=hashes.SHA256()),
            algorithm=hashes.SHA256(),
            label=None
        )
    )
    return ciphertext

# 解密函数
def decrypt_data(ciphertext, private_key):
    try:
        plaintext = private_key.decrypt(
            ciphertext,
            padding.OAEP(
                mgf=padding.MGF1(algorithm=hashes.SHA256()),
                algorithm=hashes.SHA256(),
                label=None
            )
        )
        return plaintext.decode()
    except InvalidSignature:
        print("Invalid signature, decryption failed.")

# 示例
private_key, public_key = generate_rsa_key_pair()
plaintext = "Hello, world!"
ciphertext = encrypt_data(plaintext, public_key)
decrypted_text = decrypt_data(ciphertext, private_key)

print(f"Plaintext: {plaintext}")
print(f"Ciphertext: {ciphertext.hex()}")
print(f"Decrypted Text: {decrypted_text}")