This Python script performs a simple Caesar cipher encryption and decryption on a given plaintext message. It shifts each letter in the alphabet by 13 positions to the right for encryption (Caesar cipher with a shift of 13), and reverses the process for decryption.

• Encrypts plaintext messages using a Caesar cipher with a shift of 13.
• Decrypts ciphertext messages by reversing the Caesar cipher process.
• Preserves spaces in the input message.
• Supports uppercase letters.

1. Modify the plaintext variable with the message you want to encrypt.

2. Run the script by executing the following command in your terminal:

python your_script_name.py

3. The script will perform the encryption and print both the ciphertext and the decrypted message.

Suppose you have the following line of code in your script:

plaintext = 'SELAMAT DATANG DI KELAS KRIPTOGRAFI'

After running the script, you will see the following output:

FRYNZN GNFGNA QV XRYNF XEVFCBENSV
SELAMAT DATANG DI KELAS KRIPTOGRAFI

This script is provided under the MIT License.

Replace `"your_script_name.py"` with the actual name of your script. You can further customize the README.md file to include additional information or usage examples, depending on your project's needs.