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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 _create_payload(payload):
 """Return the string payload filled with zero bytes up to the next 512 byte border. """

        blocks, remainder = divmod(len(payload), BLOCKSIZE)
        if remainder > 0:
            payload += (BLOCKSIZE - remainder) * NUL
        return payload