How do I generate a set of random variables that forms a cluster?

A set of random variable is to be generated and they are to be plotted as cluster. I've approached this using PRNG available in numpy.randint(0, 100, 500) Given the seed and the range, it gives the numbers. I'm not quite sure, do they form a cluster ? If they do, is it the scatter plot that should be used to show the cluster ? If yes, scatter plot need two variables, I've one.