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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 _prep_crypto_msg(message):
 """Split the signature and certificate in the same way M2Crypto does. M2Crypto is dropping newlines into its signature and certificate. This exists purely to maintain backwards compatibility. Args: message (dict):
 A message with the ``signature`` and ``certificate`` keywords. The values of these two keys must be byte strings. Returns: dict: The same message, but with the values of ``signature`` and ``certificate`` split every 76 characters with a newline and a final newline at the end. """

    signature = message['signature']
    certificate = message['certificate']
    sliced_signature, sliced_certificate = [], []
    for x in range(0, len(signature), 76):
        sliced_signature.append(signature[x:x+76])
    for x in range(0, len(certificate), 76):
        sliced_certificate.append(certificate[x:x+76])

    message['signature'] = u'\n'.join(sliced_signature) + u'\n'
    message['certificate'] = u'\n'.join(sliced_certificate) + u'\n'
    return message