Question $3$: $[12\mathrm{.}5$ marks$]$

You are requested to write a python program that does the following:

a$.$ Create Computation class with an initializer that takes $n$ as a parameter.

b$.$ Create a method called Factorial$()$ in the above class that takes $n$ as a parameter, calculates

the factorial of $n,$ and return $n\text{'}$s factorial.

c$.$ Create a method called Sum$()$ in the above class that takes $n$ as a parameter, calculates and

returns the sum of the first $n$ integers $1+2+3+$dots$+n.$

d$.$ Instantiate the class after prompting the user to enter an integer, $n,$ and write the necessary

statements to test the above two methods.