import Crypto
from Crypto.PublicKey import RSA

key = RSA.generate(2048)
print(key.exportKey("PEM").decode())

# 保存
with open("private.pem", "wb") as fp:
    fp.write(key.exportKey("PEM"))

# 読み込み 
key = RSA.importKey(open("private.pem", "rb").read())

publickey = key.publickey() 

with open("publickey.pem", "wb") as fp:
    fp.write(publickey.exportKey("PEM"))
publickey = RSA.importKey(open("publickey.pem", "rb").read())
print(open("publickey.pem").read())

himitsu = publickey.encrypt(bytes("あいうえお", "utf-8"), 32)
himitsu

key.decrypt(himitsu).decode()