Problem 2 (Cipher module) • Create a Python file named cipher_module.py with functions to encode and decode string inputs using the basic Caesar cipher (see here for more information https://en.wikipedia.org/wiki/Caesar_cipher). This cipher is a basic encryption technique that supports encoding and decoding operations on strings. • The encoding operation replaces each character in a string with another character some fixed number (shift) of positions down the ASCII table. The string can be encoded using any characters on the ASCII table and no need to use the circular list (where ‘Z’ is followed by ‘A’) image shown below. Your module must have a function named encode() that takes a string and an integer shift (can be positive or negative) as parameters and returns the encoded string using the shift value. This module must     Page 3 of 4 also have a second function name decode() that takes an encoded string and an integer shift as parameters and returns the decoded string. The decoding operation is the reverse of encoding. • Import your cipher_module module in another Python program named p2.py and use the functions provided by the module to test the encoding/decoding operations on some sample strings using different shift values. • Submit both cipher_module and p2.py. • Hint: use built-in ord() function to convert a character to ascii integer and chr() function to convert the ascii to a character. Sample run: cipher_module.encode(abde, 2) returns cdfg cipher_module.decode(cdfg, 2) returns abde cipher_module.encode(eebcd, 3) returns hhefg cipher_module.decode(hhefg, 3) returns eebcd cipher_module.encode(hhefg, -2) returns ffcde cipher_module.decode(ffcde, -2) returns hhefg

 

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also have a second function name decode() that takes an encoded string and an
integer shift as parameters and returns the decoded string. The decoding operation
is the reverse of encoding.
• Import your cipher_module module in another Python program named p2.py and
use the functions provided by the module to test the encoding/decoding operations
on some sample strings using different shift values.
• Submit both cipher_module and p2.py.
• Hint: use built-in ord() function to convert a character to ascii integer and chr()
function to convert the ascii to a character.
Sample run:
cipher_module.encode(abde, 2) returns cdfg
cipher_module.decode(cdfg, 2) returns abde
cipher_module.encode(eebcd, 3) returns hhefg
cipher_module.decode(hhefg, 3) returns eebcd
cipher_module.encode(hhefg, -2) returns ffcde
cipher_module.decode(ffcde, -2) returns hhefg