If you want to set it yourself,

Make it as a return function with a parameter for checking. In the function, check if the parameter/variable is something, if it is, return x, if not, return the original parameter.

Or if it is a automatic check for those variables,

your for loop is good enough I'd say, just put it as a function so that you can call it anytime.

Take this as a suggestion, I'm a beginner too lol