Python PyCrypto: Sign Data Example.py

def sign_data(private_key, hashed_data):
    '''
        param: private_key
        param: hashed_data SHA256 hash of data to be signed
        return: base64 encoded signature
    '''
    from Crypto.PublicKey import RSA
    from Crypto.Signature import PKCS1_v1_5    
    from base64 import b64encode
    key = private_key
    rsakey = RSA.importKey(key)
    signer = PKCS1_v1_5.new(rsakey)
    sign = signer.sign(hashed_data)
    return b64encode(sign)