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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def decrypt(key, ciphertext):
 """Decrypt Vigenere encrypted ``ciphertext`` using ``key``. Example: HELLO Args: key (iterable):
 The key to use ciphertext (str):
 The text to decrypt Returns: Decrypted ciphertext """

    index = 0
    decrypted = ""
    for char in ciphertext:
        if char in string.punctuation + string.whitespace + string.digits:
            decrypted += char
            continue  # Not part of the decryption

        # Rotate character by the alphabet position of the letter in the key
        alphabet = string.ascii_uppercase if key[index].isupper() else string.ascii_lowercase
        decrypted += ''.join(shift.decrypt(int(alphabet.index(key[index])), char))
        index = (index + 1) % len(key)

    return decrypted