Create the three classes shown below in figure $1$:

$1.$ PhoneDetails class, this to provide the phoneNum, with set and get functions

$2.$ Person class, to provide information as user name with set and get functions

$3.$ ServiceProvider class, to provide the name of the service provider name $($i$.$e$.$

Vodafone, BT$,$ etc.$)$ with set and get functions.

$4.$ Test your classes by creating an object for each.