Which Python version are you using to run your script, 2 or 3? This issue could because you're using Python 2 to run a script meant for Python 3. (In particular, the input function does different things in Python 2 and 3, which can cause some obscure problems.)
In general, if you're encountering a problem when running a specific piece of code, it's always a good idea to include the code in question (as long as it doesn't contain anything secret of course). If you get an error message, copy and paste it into the post as well. (If the error pops up in a red window like in your screenshot, tap on "Print Traceback" to print the error to the console in a copyable format.) For code and error messages, use code blocks (with triple backticks) as @zrzka described above. Without the code and the full error message, it's often difficult to find out what the problem is.
By the way, almost all of us on the forum here are users like you. The app is developed by a single person, everyone else on the forum is posting in their free time and isn't getting paid to provide support. Please keep that in mind when asking for help.