write pyton code for crypto

Sure, here's an example of Python code for basic encryption and decryption using the Caesar cipher:

def encrypt(text, shift):
    encrypted_text = ""
    for char in text:
        if char.isalpha():
            if char.isupper():
                encrypted_text += chr((ord(char) - 65 + shift) % 26 + 65)
            else:
                encrypted_text += chr((ord(char) - 97 + shift) % 26 + 97)
        else:
            encrypted_text += char
    return encrypted_text

def decrypt(text, shift):
    decrypted_text = ""
    for char in text:
        if char.isalpha():
            if char.isupper():
                decrypted_text += chr((ord(char) - 65 - shift) % 26 + 65)
            else:
                decrypted_text += chr((ord(char) - 97 - shift) % 26 + 97)
        else:
            decrypted_text += char
    return decrypted_text

# Example usage
plaintext = "Hello, World!"
shift = 3

encrypted_text = encrypt(plaintext, shift)
print("Encrypted text:", encrypted_text)

decrypted_text = decrypt(encrypted_text, shift)
print("Decrypted text:", decrypted_text)

This code defines two functions encrypt() and decrypt() that use the Caesar cipher algorithm to perform encryption and decryption respectively. The encrypt() function takes a text and shift (number of positions to shift each character) as input and returns the encrypted text. The decrypt() function takes the encrypted text and shift as input and returns the decrypted text.

In the example usage, the plaintext "Hello, World!" is encrypted using a shift of 3, and then decrypted back to the original plaintext. The output will be:

Encrypted text: Khoor, Zruog!
Decrypted text: Hello, World!
``