The factorial function is defined as follows: For a positive integer n$,$ n factorial $($written $"$n$!")$ is the product n $*($n$-1)*($n$-2)*...*1.$ For example, $3!$ is $3*2*1=6.$ Write a function called factorial$($n$)$ that takes a positive integer n as input and returns n$!.$ To do this, use the range function and for loops