$(20$ points$)$ Create a function FindDifference$()$ that takes in $4$ parameters:

personToColors: a dictionary that has a string key $($name of person$),$ and a list of

strings as the value $($names of person's favorite colors$).$

person$1$: a string of one person's name.

person$2$: a string of another person's name.

person $3$: a string of another person's name.

This function returns a list of all colors in person$1\text{'}$s list that DO NOT appear in either person$2\text{'}$s

or person$3\text{'}$s list.

So in this scenario:

person$1$ : $["$red$",$ "blue", "green", "yellow"$]$

person$2$ : $["$green$",$ "viridian", "cerulean"$]$

person$3$ : $["$saffron$",$ "lavender", "fuschia", "Yellow"$]$

The function will return this list: $[$ "red", "blue"$]$