Use the instructor provided xor code to implement a scheme that allows you to encrypt and decrypt some data using symmetric encryption principles.

-you can implement any scheme that you want. either one of the schemes discussed in the class or a new one that you designed on your own.

-the key aspect is that you should generate several blocks from the input and you should do several rounds of encoding.

-implement the python code and show your results.

here is the provided code:

## xor script

from os import urandom



def genkey(length):
return bytearray(urandom(lenght))



def encrypt(plaintext, key):
return bytearray([ ord(plaintext[i]) ^ key[i] for i in range(len(



def main():
mymessage = "this is the plain text"
key = genkey
cipher = encrypt(mymessage, key)
print str(cipher)
decrypted_message = decrypt(cipher, key)
print decrypted_message
if decrypted (encrypt(mymessage, key) , key ) == mymessage:
print "it works"
else:
print "somthing failed"