This module really does nothing else but XOR-ing the plaintext with the key. The key is repeated if the message is longer than the key, which means the encryption can be broken if the message is long enough. The module even helpfully adds a (partially known) string to the message. Creating a good encryption method is a task for specialists; judging from his reply to the previous review, the author probably isn't one, and judging from his module, he certainly isn't. DON'T USE.