Exercise $1$

$(40$ points$)$ Write a Python program called DeDuplication that the program takes an input list $50,11,33,21,40,50,40,40,21$ and generate an output list $11,21,33,40,50,$ which removes the duplicated elements and sorts the list. Users might give any input list. Test your program with different testcases $($provide $2$ or $3$ test scenarios$).$ In this lab, you can use a "list counter" to help you. $($Hint: In this way, you need to know what the maximum element is in the input list. Then initialize a "counting list" and count the frequency for each element. After that iterate the "counting list" and print the elements whose frequencies are not zero.$)$