Strings don't have a contains() method. Assuming that mystring is
actually a string, you should be getting a very specific error,
telling you exactly what's wrong with your code (something like
AttributeError: 'str' object has no attribute 'contains').
If that isn't what you're seeing, you'll need to provide the full and
complete text of the error you are getting, and preferably enough of
your code that we can reproduce the issue and help you solve it.
--
Jerry