I need to encrypt a small string in Python. Is it possible to use a secret key to encrypt the string? Is there a good way to do this and achieve a reasonable encryption leve
Take a look at py-bcrypt. Perhaps it will meet your needs. From the web site:
py-bcrypt is a Python wrapper of OpenBSD's Blowfish password hashing code, as described in "A Future-Adaptable Password Scheme" by Niels Provos and David Mazières