You've collected data on an optics experiment you're conducting and have titled the plot "Experiment: focal point of an unknown lens." You then decide to duplicate the experiment to test the validity of your experimental method. Not wanting to type the same plot title over and over again with different experimental numbers, you decide to create a plot title that allows for a variable experiment number such that it reads "Experiment X: focal point of an unknown lens," where the $"$X$"$ is replaced with the experiment number that is input in the variable experiment$\_$number. The original plot title is provided for you to use to construct your new, flexible plot title. Input a number for experiment$\_$number and have the cell output the new plot title.