Problem $3$: Unique Elements Finder

Write a program that finds unique elements from a list of numbers provided by the user.

Create a function find$\_$unique$\_$elements$($numbers$)$ that takes a list of numbers and returns a new list containing only the unique elements.

Use a loop to repeatedly ask the user for numbers until they type $$done$.$

After the input phase, call the function and print the unique elements found.

$$

Enter a number $($or 'done' to finish$)$: $1$

Enter a number $($or 'done' to finish$)$: $2$

Enter a number $($or 'done' to finish$)$: $2$

Enter a number $($or 'done' to finish$)$: $3$

Enter a number $($or 'done' to finish$)$: done

Unique elements: $[1,2,3]$