pycrypto encrypt and signature demo

from Crypto.PublicKey import RSA
from Crypto import Random
from Crypto.Signature import PKCS1_v1_5

random_generator = Random.new().read
key = RSA.generate(1024, random_generator) # private key
public_key = key.publickey()
enc_data = public_key.encrypt('abcdefgh', 32)
key.decrypt(enc_data) # 'abcdefgh'

signer = PKCS1_v1_5.new(key)
sig = signer.sign('abcdefgh')
digest = SHA256.new()
digest.update('abcdefgh') # get hash of the string data
sig = signer.sign(digest)
verifier = PKCS1_v1_5.new(public_key)
verified = verifier.verify(digest, sig) # True