Implement Vernam Cipher Encryption and Decryption in Python

[Ninja-06]

Is your feature request related to a problem? Please describe.
Python_programs folder don't have vernam_cipher code.

Describe the solution you'd like
so i want to contribute code to this repo which encrypts and decrypts data using vernam cipher

Describe alternatives you've considered
Vernam cipher is not one of the best encryption method.

[Ninja-06]

Hi @fineanmol please assign this issue to me under hacktoberfest