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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(self, encryption_key, iv, encrypted_data):
 """Decrypt encrypted subtitle data @param int subtitle_id @param str iv @param str encrypted_data @return str """


        logger.info('Decrypting subtitles with length (%d bytes), key=%r',
            len(encrypted_data), encryption_key)
        return zlib.decompress(aes_decrypt(encryption_key, iv, encrypted_data))