def encrypt(self, data, pad=True):
encrypted_data = b"<STR_LIT>"<EOL>for i in range(<NUM_LIT:0>, len(data), <NUM_LIT:8>):<EOL><INDENT>block = data[i:i + <NUM_LIT:8>]<EOL>block_length = len(block)<EOL>if block_length != <NUM_LIT:8> and pad:<EOL><INDENT>block += b"<STR_LIT:\x00>" * (<NUM_LIT:8> - block_length)<EOL><DEDENT>elif block_length != <NUM_LIT:8>:<EOL><INDENT>raise ValueError("<STR_LIT>"<EOL>"<STR_LIT>")<EOL><DEDENT>encrypted_data += self._encode_block(block)<EOL><DEDENT>return encrypted_data<EOL>
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