using function to encrypt/decrypt a string

I'm tryna figure out how to encrypt/decrypt a string using a single function that takes a string and an offset as parameters. depending on the offset, the function encrypts or decrypts and builds new encrypt/decrypt string

Thanks a lot!

yeah so this is what the task is asking. I'm doing it atm

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Solution

It seems like what you want is a caesar cipher which is relatively simple to do in python.

def encrypt(text, key):
    """Encrypts text using a ceaser cypher"""
    encrypted = ""
    for char in text:
        if char.isalpha():
            encrypted += chr((ord(char) + key - 97) % 26 + 97)
        else:
            encrypted += char
    return encrypted

The only really weird part about this code is the unicode character madness. If you don't know unicode/ascii is a way to map numbers in a computers memory to characters which computer memory is fundamentally just 1's and 0's. here's a chart for all the relevant character