http://example.com/test/?code=this_is_safe_code. The code would be evaluated.
I don't want outside users to be able to send code through, though. I want all requests made to be internal. Since I know the internally transmitted code will be a safe mathematical expression, I feel comfortable using
eval. However, if someone from the outside sent something like
http://example.com/test/?code=__import__%28%22os%22%29.system%28%22echo%20DANGER%22%29, then Python would run
__import__("os").system("echo DANGER"). Which is obviously not safe.