In this problem, you'll implement a simplified version of a stream cipher. Remember that a stream cipher encrypts plaintext by combining it with a keystream $($a pseudo$-$random sequence of bits$)$ to produce the ciphertext. The encryption and decryption processes are identical, except for the input data.

Things to do:

$1.$ Keystream Generation:

$-$ Write a function generate$\_$keystream$($length$)$ that generates a list of random integers between $0$ and $255($inclusive$)$ to match the ASCII range.

$-$ Make sure the keystream is the same length as the plaintext.

$2.$ Encrypt Function:

$-$ Implement an encrypt function that takes plaintext and keystream as inputs.

$-$ Convert each character of the plaintext to its ASCII integer value and then XOR with the keystream to produce each character of the ciphertext.

$3.$ Decrypt Function:

$-$ Implement a decrypt function that uses the ciphertext and the same keystream to retrieve the original plaintext.

$-$ Since XOR encryption is symmetric, applying XOR with the same keystream to the ciphertext will recover the plaintext.

$4.$ Test the Program:

$-$ Test your program with some test cases and mention them in the abovementioned document.

$-$ You must demonstrate both the encryption and decryption output to receive full marks.