The S4 object class has a generic function equivalent to the print() generic function for the S3 class of objects. The function "show" is a generic function that works similarly to the print() function in the S3 system. You will write a method for the "show" function for the "robustSummary" S4 class as follows:

    setMethod("show",
               "robustSummary",
              function(object) {
                cat("The median is ",object@median, " with median  
                absolute deviation (MAD) = ", object@mad, "
")
                cat("First and Third Quartile is", object@q1, "and",  
                object@q3)
              }
    )