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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 encrypt(self, data, pad=True):
 """ DES encrypts the data based on the key it was initialised with. :param data: The bytes string to encrypt :param pad: Whether to right pad data with \x00 to a multiple of 8 :return: The encrypted bytes string """

        encrypted_data = b""
        for i in range(0, len(data), 8):
            block = data[i:i + 8]
            block_length = len(block)
            if block_length != 8 and pad:
                block += b"\x00" * (8 - block_length)
            elif block_length != 8:
                raise ValueError("DES encryption must be a multiple of 8 "
                                 "bytes")
            encrypted_data += self._encode_block(block)

        return encrypted_data